Answer the questions as naturally as you can. You don't want to sound like an actor delivering memorized lines. Everyone in the room, especially trial counsel, is watching you testify. They not only listen to your word, but watch how you present them. You must be as relaxed and natural as possible.
Body language is a powerful communication tool.
Use it properly. What you say will be taken down by the court reporter, later transcribed onto a printed page. It is difficult to transcribe a nod of the head or shrug of the shoulders. If the answer is ''two and one half feet,'' Say so. Only one person can speak at a time.