How to give a mathematical talk that is not too bad

Let's "define" the class of bad talks as follows: a bad talk A is worse than a bad talk B if and only if A is longer than B.* According to my experience, a frustratingly large percentage of all mathematical talks are bad, and that's because of a handful of ever recurring reasons. This percentage is not considerably lower for experienced speakers. As a desperate attempt to change this situation, I decided to write down what I have learned from my own and others' mistakes.

How to use this page: click on each of the captions below that do not make you think "yes of course". Come back and have a quick look at this list each time you are about to prepare a new talk.

• Preparing the talk

  • Adapt the talk to the audience
  • Start your talk by motivating it
  • Don't start with definitions
  • First prepare the central ideas, then extend with details
  • Balance the ingredients: theorems/proofs/examples
  • Slides: don't make too dense - leave important things there
  • Rehearse

• During the talk

  • Stress the points that nobody should miss
  • Give opportunities to catch up
  • Be fast on easy parts and slow on hard ones
  • Don't talk with a monotone voice
  • Don't let a silly detail ruin your talk

• After the talk

  • Give me some feedback about this text and forward it if it helped you