1. Dress neatly. You want to be sure your appearance and manner does not distract the jury or judge or makes your testimony seem less valid.
2. Always tell the truth. This is the single most importance piece of advice. If you do not remember something, it is alright to say so.
3. Be prepared. Think about the answers you will give to the questions you probably will be asked beforehand. Listen carefully to the entire question before you answer. If you do not understand a question, ask that it be explained before you answer. Beware of questions involving distance or time. If you can make an estimate, be sure it is understood that you are only estimating.
4. Stick to the facts. Answer only the question that is asked of you. Don't elaborate. If you can answer with a simple "yes" or "no," you should do so.
5. Relax and speak clearly. Speak loudly enough that the entire jury and court reporter can hear what you say. Use spoken answers. Do not shake your head or answer with "huh, huh."