Use vocal variety moderately. Remember to speak as if you're talking only to one person, not to an audience of thousands. Varying your pitch, volume and vocal variety too much will only annoy your audience and make you look foolish. During the program, avoid coughing, tapping your fingers, rustling paper or hitting the microphone. And watch what you say - always assume the microphone is on.
Visual aids can greatly enhance any video presentation.
Slides, photographs, film, and three-dimensional objects can illustrate your points and add emphasis to your message. Just be sure that any visual aid relates to your subject and will be seen and understood by your audience. Visual aids for video have special requirements. Video pictures are in a format of three units high and four units wide. If they're too big, they'll be cut off.