Your style and appearance really don't matter, since everyone will be riveted by your every word. They'll never even notice you're wearing tennis shoes with your suit. Don't be enthusiastic . Speaking in a droning monotone forces your audience to pay more attention. Never include graphics in your slides .
Graphics are cheap and unprofessional and only serve as a crutch.
If the audience can't get the gist of the text on each slide, that's their problem, not yours. Also, use the smallest font possible and cram as many words as you can onto each slide. If the audience isn't squinting, they're obviously not paying attention. Speak quietly . Microphones are for wimps.