Public speaking has never been my forte. As a child, I often preferred blending into the crowd rather than standing out.1 However, I’ve since realized that in the pursuit of professional excellence, there is no way to avoid the public eye. Talent and hard work doesn’t really matter if I can’t properly package and present my work to the masses. I recently defended my PhD thesis,2 so I want to take this time to reflect on what I’ve learned while delivering a few technical talks. Upon reflection, I notice that the last 5 years of PhD have made me going from shaky voice and incoherent ramblings, to the point in which it looks like I’m confident at public speaking. In this article, I sit over the shoulders of giants to tell you about some of the tricks I’ve learned from my own experience and also from great speakers. I’ll walk you through some effective strategies for technical presentations. If you follow me, I’ve no doubts you’ll be able to nailing your next one.
TL;DR: I believe that the secret to delivering a great technical presentation is feeling in control. This enables the necessary confidence to communicate effectively, and it also helps to be perceived as an expert.
Why is this important?
Professionals shouldn’t go out into life without the ability to communicate. This is because success in life is largely determined by our ability to speak (\(S\)), write (\(W\)), and the quality of our ideas (\(I\)), in that order.
Here’s an obvious oversimplification of success:
\(Success = a * S + b * W + c * I\), where \(a > b > c\).
The quality of \(S\), \(W\), and \(I\), is largely determined by how much knowledge (\(K\)) we have, how much do we practice (\(P\)) with that knowledge, and our inherent talent (\(T\)).
Here’s another simple formula for quality:
\(Quality = x * K + y * P + z * T\), where \(x > z ~\& ~y > z\).
Corollary: You can get a lot better than people who may have only inherent talents if you have the right amount of knowledge and the ability to transmit your own ideas in a better way.
As a professional, you probably want to get the maximum opportunity to have your ideas valued and accepted by the people you speak with. I argue that one of the best ways to do that by delivering excellent technical presentations.
Here’s what I think a technical presentation is:
“A technical presentation is a communication session in which a speaker delivers specialized information, explanations, or demonstrations on a specific technical topic to an audience.”
The following are the important keywords in the definition above:
“communication session” It refers to the format of the presentation. For example, conference talks, tech workshops, webinars, product sales pitches, and even job interviews are all technical presentations.
“specialized information, explanations, or demonstrations” It refers of the type of content that is delivered. In this article, I focus on technical content in the area of Computer Science and Software Technology. Technical presentations often involve the use of visual aids such as slides, diagrams, code snippets, demos, or videos to support and enhance the content reception experience.
“audience” The audience is the speaker’s target. It can be a small group of people in a classroom, or thousands in a stadium. Here I’m assuming that they are already familiar with the topic of the presentation, and that are interested on it.
NOTE: The rest of this article is written from the perspective of the speaker.
How to Start
The best way to start a technical presentation is with a factual promise.
You want to explicitly tell people that they’re going to know something new at the end of your presentation that they didn’t know at the beginning.
For example, you can claim something like: “At the end of this
X minutes, you will know things about
Y you didn’t know, and something among those new things will make a difference for you in
This is a simple and powerful statement.
Make sure to deliver your crafted hook loud and clear to the audience, so they know exactly the reason for being there.
Alternatively, you can start with a hilarious story. The easiest subjects to start with are stories about your practical experience with some modern technology or tool. For example, something like “How Docker Helps Us Optimize Delivery” or “Apache Spark Issues We Have Dealt With.” Describe what you’ve done on a recent project and what you’ve learned from it. The most important aspect of the story is the problem you’ve faced and why it’s important to solve it. Remember, it doesn’t really matter the details of the story. What matters is that there is a problem out there that needs to be solved.
I suggest putting in the first slide a title, as well as a list of collaborator or institutions that made your work possible. The second slide should contain a picture linked to the promise or the story you’re talking about. I don’t like the idea of showing an outline with bullet points of whole content (sometimes titled “Agenda”), some people do, but it’s boring. Instead, announce the structure out loud, multiple times, during the presentation.
⚠️ Patrick Winston wisely suggests: “Don’t start the presentation with a joke. The reason is that, in the beginning of a talk, people are still putting their laptops away. They’re becoming adjusted to your speaking parameters, to your vocal parameters, and they’re not ready for a joke. So early jokes doesn’t work very well.”
Time and Place
The best time for delivering a technical presentation is the morning, usually around 11:00. The reason is that most people are awake by then, people aren’t fatigued because they’re expecting lunch. The worst time is after lunch, at that time everybody feel tired and sleepy.
The best place is a theater with at least 100 seats. I’ve noticed that the most people are in the room, the easier the job is for me as speaker. Large audiences make me feel empowered, like if I’m giving a discourse. Also, a larger audience makes less likely being interrupted by an unexpected question.
It is important to turn on the lights in the room, and making sure there is a clock visible somewhere. The reason for the first is that we humans, whenever the lights go down, it signals that we should go to sleep. The reason for the latter is that time is super important, and you want to make sure you’re not going over time.3
I recommend going to see the place before the actual talk to make sure you know about any potential issue in advance. This way there will be no surprises. Sometimes preparing the place might require some intervention from you. In most cases, you just need to be aware of what the challenges are.
There are three key instruments you can use: boards (for informing), slides (for exposing), and props (for demonstrating).
We all know about boards and slides, but sometimes we forget about props.
These are tools or accessories that you can use to make sure your talk is memorable.
Props are ofter useful for showing the importance of looking at the problem in the right way.
For example, a demo is a powerful prop you can use.
I firmly believe that there’s nothing like running code to enhance the quality of a presentation.
By running code, the people in the audience will feel that you’re actually doing something real.
It’s not just a bunch of slides
that anybody alse can prepare.
Regarding slides, there’s always too many, and they have always too many words. So, I recommend going over the following checklist after you have prepared the first deck of slides:
Don’t use many words on each slide. How many? I’d say 42 words per slide is the absolute maximum 😄. By reducing the number of words on each slide, you’re allowing your audience to pay more attention to you and less to what’s written on the slide. You want to be the focus of your audience. Remember that we have only one language processor, and we can either use it to read stuff or to listen to the speaker. And so if we have too many words on the slide, it forces people in the audience to read this stuff and not listen.
Don’t read. People in your audience know how to read, so reading will just annoy them. Use the slides as a condiments to what you’re saying, not as the main course.
Don’t use any background junk. Aim for simplicity and remove any source of distraction. This includes any logo, title, or even these bullets in a list of items.
Don’t use any kind of laser pointers. Those are distracting because you lose the contact with your audience, instead, use animations. For example, just put a little arrow on the elements your want to focus on, and tell the audience to look at that.
Make sure you make good use of the following four tricks:
Mere repetition. Tell what you want to tell and go around it. Tell it again, and then tell it a third time, as if people weren’t smart enough to understand it. The point is that, at any given moment, about 80% of the audience will be fogged out no matter what. Therefore, if you want to ensure that the probability that everybody gets it is high, you need to say it three times.
Claimed originality. Explain you core idea in a way that it cannot be confused with somebody else’s idea. For example, you could say: “Well, my algorithm might seem similar to Alice’s algorithm, except hers is exponential, and mine’s linear.” Put a fence around your idea so that people can not be confused about how it might relate to something else, or even worse, someone else’s work.
Strategic emphasis. People will occasionally fog out and need to get back on the bus, so you need to provide some landmark places where you’re announcing that it’s a good time to get back on. For example, a big text with the section title as transition provides a sense that there’s a structure in the talk, and you can get back on anytime.
Provocative Questions. Prepare a few provocative questions in advance. Make sure the questions are not so easy because people will be embarrassed to answer it, nor so hard because then nobody will have anything to say. Throw one question at the time and wait, don’t say anything for 7 seconds (that’s the maximum amount of time you should wait for an answer). If nobody answers (red flag), then you can answer it yourself.
Watch the speakers you admire and feel are effective, then ask yourself why they’re successful. Copy them first, the way they move, the way they talk, the way they use their hands, and so on. Then, you can start to modify it and make it your own style. Your personal repertoire of gestures and movements will grow over time with practice. It’s just like learning a new language.
Many people who are novices at speaking find themselves suddenly aware of their hands.
Here are some personal tricks from professors I had around that have caught my attention:
- The way Martin Monperrus uses pauses to create suspense (Example).
- The way Benoit Baudry uses his hands to explain things (Example).
- The way Andreas Zeller uses stories to support a flow of arguments (Example).
How to Inspire
Turns out that people are inspired by different things depending on their age or current status. For example, graduate students are often inspired by some high school teacher who told them they could graduate. Professors are often inspired by someone who helped them see a problem in a new way. Entrepreneurs are inspired by self-made millionaires. And so on. Something common from everyone is getting inspired when someone exhibits passion about what she or he is doing.
One way to inspire people is by telling personal stories.
It always works because people are inherently curious.
The story needs to be
These stories can help them understand different situations and emotions, learn lessons, and get ideas.
Another way is by creating a situation.
Describing a situation is good because it allows putting your topic in context.
For example, you can say something like “This is a problem that’s being pursued all over the world. However, there hasn’t been any progress in the past
X years, so everyone is looking for a solution because it will have impact on
Everyone will be interested.
Q: Why do you want recognition for what you do?
A: Simply because no one gets used to being ignored.
You will get recognized by being remembered. How do you get remembered? One of the things you need to do is to make sure that you have some kind of symbol associated with your person or your presentation. Next thing you need is some kind of slogan, a kind of phrase that provides a handle on your work. And now we need a surprise. Next item was a salient idea. A single idea that sticks out.5 And finally, you need to tell the story of how you did it, how it works, why it’s important.
You already know that practice is important, but here’s some extra advice: Don’t show your slides to the people you will present to. If they know what you’re doing, they will hallucinate that there’s material in your presentation that isn’t there. The best way is to get together with some friends who don’t know what you’re doing and practice with them.
Start your practice session by saying: “If you can’t make me cry, I won’t value as a friend anymore.”
Here’s another nugget: The amount of feedback you’ll get from somebody is proportional to age. The older somebody is, the more they understand where they are in the world. But the young people are trying to show the old people how smart they are, it’s subtly vicious. Whenever you have an opportunity to have an examining committee that’s full of people with gray hair, that’s what you want.
Job presentation deserves a special section because they are so important. It’s basically a sales pitch in which you have to quickly convince a few people (hopefully your potential managers) that you are the right person for the job.
If the market needs you, the employer will trust you more. That’s exactly what you need in order to request a higher pay. You need to tell them about your vision, and that you’ve already done something. If you cannot make these two points in 5 minutes, you’ve already lost.
Concretely, you have 5 minutes to:
Show you have some kind of vision. By expressing your desire to work on a problem that somebody cares about, and that there’s something new in your approach.
Show you have done something to solve a problem. By providing a list with the steps that need to be taken in order to realize the vision. You don’t have to have done all of those steps. But you can say something like: “here’s what needs to be done.”
Here’s an example:
|Problem||Vision||To Be Done|
|Maintaining large codebases||To develop and integrate AI-powered tools into the software development process to automatically suggest how to isolate pieces of code and repackage them as independent components (a.k.a libraries).||We need to 1) choose the right AI technique giving the problem’s constraints, 2) specify when to split the codebase, 3) build the system, 4) showcase a PoC of such a system, and 5) |
Be prepared to have a good list of interesting problems. For example, here is a list of research topics that I’ve compiled.
How to Finish
One of the best ways to finish is by telling a joke. By the time you’re done, people have adjusted themselves to your voice parameters. They’re ready for a joke, and that way, people think they’ve had fun the whole time.
⚠️ Again, as Patrick Winston said, finishing with “Thank you” is a weak move. When you say thank you, it suggests that everybody has stayed that long out of politeness and that they had a profound desire to be somewhere else. But you are not taking their time, you are giving them something. So don’t say thank you before the wild applause.
Your last slide is an opportunity for you to tell people who you are and what you have done. And that’s why your final slide should be labeled as “Contributions.”
Finally, the last thing you could do is to salute the audience.
Here are some of the best presentations I’ve seen:
- “Steve Jobs Introduces iPhone in 2007” (10 min)
- “The Future of Programming,” by Bret Victor (32 min)
- “The Mess We’re In,” by Joe Armstrong, creator of Erlang (45 min)
- “The Art of Code,” by Dylan Beattie (1h)
- “The Deep Synergy Between Testability and Good Design,” by Michael Feathers (50 min)
The way you present and how you package your ideas is a fundamental skill. It measures your caliber as a professional. As a result, a big chunk of life’s success depends on it.
The quality of communication is determined by knowledge, practice, and inherent talent, with talent being the less important factor. Effective communication involves clear explanations, using appropriate language, and ensuring that the audience understands the message. For this you can use slides, props, and gestures, but nothing is better that language to deliver communication and aid understanding. The use of slides in presentations should be optimized by reducing text, using larger fonts, eliminating clutter, and focusing on conveying key information.
Develop your own style. For example, by incorporating storytelling and asking thought-provoking questions can stimulate curiosity and enhance engagement. The use of personal stories helps to inspire and connect with the audience. It also helps to study carefully what the best speakers do.
That’s all from me, the rest you can probably only learn it by doing it.
Feeling ridiculous is perceived as a big problem at young ages. ↩
It went well, if you ask me. ↩
Going over time is one of the worst crimes of a public speaker. ↩
Surprisinglymost people don’t understand code. Showing some code is a guarantee of being perceived as expert. ↩
Some speakers, funnily enough, have too many good ideas, and you don’t know what it’s all about because… which one is the good one? ↩