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How NOT to do slide presentations

Gabriel Cruz
6 min readApr 2, 2019

I am not an expert on psychology or design but I have watched hundreds of slide presentations throughout my life and I think some things need to be said before is too late.


  1. Think carefully before using slides.
    Is there any other tool you could use to get the job done?
  2. Keep your slides simple
    Don’t put too much information on a single slide
  3. Slides are not supposed to be text screenshots or studying material.
    Want to show text? Use text documents.
  4. End strongly
    Make sure you leave a message

Why I am writing this

To be honest, I don’t know anyone that is more annoyed with slideshow presentations than me. Don’t get me wrong, they are great sometimes: they help to visualize data and make great impact on the crowd. But I (very) often see them being poorly used.

In my university there is a huge number of professors that use slides in their lectures, and it’s got to the point where slides are the standard go-to tools for preparing and teaching a lecture. Problem is: they are usually not the best tool for the job.

If you ever watched any TED talk, even though some are way better than others, you probably know what good slideshows (and good talks in general) look like. And if you ever watched any other presentations you probably bumped into a few that are far worse than TEDs’. The question you got to ask yourself is “why”?


This post is 90% based on my own personal opinion and experience and 10% common knowledge. Some of what will be said is not necessarily always true — although most of it applies in most cases.

A shitty presentation

Let’s take a look at a lecture on, say, pooping.


The only problem that an opening slide can have is the title. Titles are supposed to be short and intuitive.

It’s not the best opening you will ever see, but it’s simple and it does the job. Putting your name on the slides doesn’t add important information to them, although this is not that big of a deal.

Summary (???)

I personally love summaries. They are really useful on books and other WRITTEN material when you need to find a specific content or topics. Slideshows, however, are not books — the audience can’t simply skip parts of the talk or go back whenever they want. Presentations are more like movies: you enter the room, sit and watch (and, if you are lucky, enjoy). Have you ever seen a summary at the beginning of a movie, even if it’s a documentary? That’s right.

The question you got to ask yourself: is it important for the audience to actually know the order of the topics you are going to talk about? What good does that do?

Although there would be an argument to be made to use summaries in order to explain what the presentation’s topics are and what it is mainly about, people are supposed to know that beforehand, not after they made time for it and rescheduled their important appointments to watch it.

Even if they forgot the exact list of everything you are talking about, they don’t care. They only remember that, at first, your talk seemed interesting. All a summary does here is make your talk feel like a task that you and your audience have to go through and get over with.

Here’s an example of good summary:



I always thought of introductions as useless, purposeless things, but that is probably because I was used to seeing shitty introductions. Introductions are supposed to pose the questions about the problem we are presenting. What comes after is the process of trying to figure out answers to these questions.

Shitty introductions usually repeat what is on the summary (if there is any) and add a little bit of useless information.

You will see that I find most information useless, that is because I believe slides are not supposed to carry much information, but rather to illustrate what is being said.

Another important detail I didn’t mention so far is that sections shouldn’t need to state what they are. For example, the introduction’s title shouldn’t need to be “Introduction”. It makes literally no difference to the audience which section it is, all that matters is content.

“But you said slides should have content”

Right, it should. But it shouldn’t have bullshit. The rest of the content is up to you to say. If what you have to say doesn’t add value to your presentation, then it shouldn’t be a presentation.



Topics are supposed to be short god damn it! Don’t put everything on one slide. One of the things that annoys me the most is spending too much time in one single slide.

In other words, do not do this:

I made all these up, though some of it may be true

Here is how I would do it:

First, introduce the topic
Split topics between slides
Group closely related information

Don’t be afraid to make more slides if you need to, just make sure each of them contains a clear, concise message. Be careful not to mix different topics, develop one idea per slide.


Making jokes is not only important, but necessary. Images are great for that, use them in incremental slides to loosen up the mood. There is no bad example here. A bad example would be not to make any jokes.


End with impact. I’m not a fan of “Thank you” slides at the end of a presentation. Do say “Thank you”, but don’t spend a slide on it. Instead, leave the crowd with a power statement or a catch phrase.

Use this:

Instead of this:

Thank you.



Gabriel Cruz

Computer Science student at University of São Paulo. OSS/Linux enthusiast, trailing spaces serial killer, casual pentester