Your slides are not your talk
While it is tempting to spell out everything in full detail on
the slides, remember that the slides are not your presentation.
The slides are merely there to support your presentation.
Rule #1: What do you want to say?
Be very clear: what is the point you're trying to make with this
bullet point (or even: with this slide or with this part of the
If you can phrase that succinctly for yourself, then you can
explain it well in the presentation.
Rule #2: Why do you want to say this?
Now that you know what you want to say, ask yourself: why should
the audience hear this? How does this fit in with the rest of
Asking this question can help you to not go too deeply off on a
tangent that, while interesting, ultimately is a distraction
from the main message of your presentation.
Timing: 1 min / slide
You will want to know how many slides you will need to fill the
allotted time, without going too much over or under. A general
rule of thumb is to count one minute per slide. If you have a
few slides more than minutes, you'll probably have to speed up
at some point.