(Not mine, but I found it and thought it might be useful for others... if you've got other tips to deal with exam anxiety, please post!!)

Strategies for Reducing Exam Anxiety
Stress is universal. Everyone experiences it, to some degree. Although you can't always avoid stressful situations, you can take steps to control your stress and anxiety in such situations. Here are some strategies to help reduce exam anxiety.


BEFORE THE EXAM: Prepare

• Learn and review as you go. Don't leave all your studying til the last minute.
• Know when you know. Test yourself often on course material. Don't just read and recognize!
• Find out how you will be tested and prepare by answering that kind of question: solve problems, explain/compare theories, apply theories to situations, etc. Practise without notes or your textbook and with a time limit, just like on the exam
• Set realistic and achievable goals. don't be a perfectionist who tries to learn everything. and don't tell yourself that you have to "ace" every exam.
• Eat and sleep well before an exam.
  

DURING THE EXAM: Be positive and strategic

• Think positive thoughts at the beginning and throughout the exam. Tell yourself that you are prepared, you can do it, you deserve to succeed, you'll get at least part marks on hard-to-do questions, etc.
• Remember that your future does not depend on the specific outcome of a specific exam.
• View exams as an opportunity to show what you know.
• Use effective test-taking strategies
  

LEARN AND USE RELAXATION TECHNIQUES

• Learn to relax your body by using deep breathing and muscle relaxation.
• Prior to an exam, visualize yourself relaxing and coping successfully during the exam.
• Visualize stress-provoking situations and rehearse mentally how you will handle them and control stress.