Beyond Bullets presents a good powerpoint cooking recipe:

Reduce visual overload by moving text off-screen, and shift processing to the auditory channel by narrating the content instead. A practical solution in PowerPoint is to approach each slide from the Notes Page view first, placing written explanation in the off-screen Notes section below, and using the on-screen area above for an illustration and a few descriptive words. This solution offers a better projected media experience, plus more comprehensive handouts when the PowerPoint is printed in Notes Page format. (...) If you’re short on time, here are five tips to help you apply Rich's research-based design principles to PowerPoint: 1. Do your slides contain only words? Show some pictures. 2. Do your slides contain words that you also speak? Stop being redundant. 3. Do your slides contain things you don’t explain? Get rid of them. 4. Do you pause for a long time on a single slide? Break it up into smaller pieces. 5. Do you have lots of information on a slide? Keep it simple.