Sam Nelson - Tips for giving a good talk

Tips for giving a good talk

While not meant to be comprehensive, the following is a list of a few tips which can help to improve the quality of a mathematical or other formal talk.

Prepare a script. Even if you know your subject like the proverbial back of your hand, it can be very easy to get nervous, intimidated, or just confused during your talk. After all, you're under time pressure, and the audience can include world experts in your field who very likely know much more about your subject than you do, which can be intimidating. Having a script ready means you can pick up where you left off if you get mixed up, and nothing says you have to follow it precisely -- but it's important to have it in case you need it.
Make slides. Writing on the board is very time-consuming and prone to errors, especially when you're under time pressure and nervous. Preparing slides beforehand not only gives you the chance to edit what you show the audience in advance, making sure you catch and correct errors, but saves you the time of having to copy onto the board. Also, it's generally easier to read typed slides than handwriting. Preparing slides forces you to organize beforehand what you plan to say, so that your talk has a better chance of sounding like a coherent talk instead of disjointed rambling.
I used to use overhead slides (aka transparencies) prepared with LaTeX, though these days my preferred format is a landscape .pdf file on a USB stick, prepared with LaTeX -- it's pretty unusual these days to be asked to give a talk in a room which doesn't have a computer and projector. One can opt for an old-school look with SliTeX, or for a more modern look use the Beamer package.
For the LaTeX-impared, another option is to use PowerPoint (or OpenOffice), though if you opt for this route I urge you to resist the temptation to fill your presentation with distracting fades, special effects, and little dancing monkey animations.
Whatever softare you use to prepare your slides, it's a good idea to make a self-contained .pdf file in case the computer you're presenting on doesn't have your fonts or software installed. It's also a good idea to have a printout of your slides for use with camera-type projectors in case of computer crashes.
Slides are not your script. Your slides should be the illustrations of your talk, not the complete talk itself. Too many words on a slide are distracting and the audience ends up reading your slides instead of listening to your talk. You should have a title slide listing your name, the title of your talk, and your academic affiliation as well as any other relevant information like faculty mentors, coauthors or funding information. The rest of your slides should have the main points of your talk, including short statements, diagrams, equations, statements of theorems and sketches of their proofs, and computational results.
Practice your talk. Going through your talk in front of actual live people can help you catch errors or omissions and give you a good idea of how much time your talk will take. It can also help you to anticipate questions that your audience will have, including the ubiquitous "What are the practical applications of your research?" question.
Appearance. It's not always necessary to dress up formally in a suit and tie, but it is important to calculate the effect your appearance will have on your audience. When in doubt, it's best to err on the side of formality, and in any case one should always try to look good. Dressing up, even if only slightly, sends the message that you're aware that you're not in everyday mode but are taking the conference seriously.
Attend the other talks in your session. If everyone skipped all the talks but their own, there'd be no point to having a conference. Part of what's good about going to conferences is getting to see what other people are doing and how they're approaching their research problems in order to get new ideas for your own research. This also solves the problem of getting lost in the building (unless you're scheduled to talk first) and makes it easier to deal with unanticipated schedule or room changes.