Posters are an important form of scientific communication, and you will make many posters over the course of your career. There are two parts to a poster presentation: designing the poster before the meeting, and presenting it once you are there. Here is some advice that I have collected to help with each step.
Here is some good general advice on posters from some Informatics students. Includes advice about how to print posters locally.
Here is some other all around advice on presenting an academic poster.
For advice at a more philosophical level about how a poster is used in communication, see Ten Simple Rules for A Good Poster Presentation. Also, if you will use figures on posters (Hint: you will), also see these Ten Simple Rules for Better Figures.
For those who prefer sarcastic anti-adivce, please see this advice on how best to commit Mortal Sins in Poster Presentations or How to Give the Poster No One Remembers
This blog about scientific posters has some amazing examples as well as critiques that show the process of posters being improved. NOTE: Some of the examples on this blog are probably better designed than any poster I have ever personally seen in a decade of attending conferences.
As for the mechanics, here are tips on how to use PowerPoint for posters. Back when I made posters, I found that PowerPoint was OK but had some annoying features. Lots of people use LaTeX which works well, although I prefer specialized desktop publishing software.
Some other suggested pages:
beamerpostertemplate is a popular option for LaTeX posters. Here is another LaTeX poster template with some nice examples. Within Informatics a lot of people use the infposter class with LaTeX
One more point that I'd like to make that I didn't see above. We often talk about "a poster presentation," but this is misleading. In fact, you use your poster for many different presentations, depending on who you are talking to:
You want your poster to work for all three types of presentations. I like to have enough text on the poster that it can be read usefully if I'm not around, but enough tables and equations that I can give a presentation that ignores all of the text. But not too much text. Your text should be big and simple. You should not copy sentences from your paper; these sentences will usually be too complex. Your poster should have strong visuals.
Be aware that your presentation should be an interactive discussion. Sometimes you will be talking to one or two people, and sometimes a crowd. If only a few people, watch them closely to judge when you should give more detail and when you should speed up.
Also, the easiest way to proofread a poster is to print it in colour on a sheet of A3 paper. As an American, I find ISO paper sizes to be particularly refreshing here.
Thanks to Teresa Ironside, Kenny Bell, George Papamakarios, Kevin Ashley, Michele Volpi, Alyssa Alcorn, and Myroslava Dzikovska for suggestions that led to this page.