The article Stop Death by Power by Christian Buss talks about the mistakes people make when using Powerpoint . First one is the presentations are too linear and the audiences know what to expect so you have to try to make it a little more different.
Second don't write what you are about to say on the slide since the audiences can read them faster than you can say them out loud so they will be bored until you finish talking.
Third :Limit each slide from 30 to 60 seconds so you won't produce a mind dump .
Fourth : don't read the titles your audience probably did that allready and it takes away from the value and don't overclutter the presentation or add too many annoying animations.
Fifth : Before the audiences settle talk to them so you know what might concern them . Have a question and answer session and a ) omit a piece of key information so they will ask about it or b) tell some d from the audiences to ask a couple of questions so your question and answer session will be nice and interactive.