Simplify your frame. Think about where everything is going to be. People coming in and out of the frame can create movement that may cause confusion. A lot of auto-focus cameras can't focus properly if you are too close to your subject. Five or six feet away is a good distance.
Good lighting is essential .
Try to light your scene from the front. Try shooting outside if possible. Use the fastest record speed . This will insure the best video quality. Hold the mike close to your mouth to cut down on external noises.