Before the test:

• Be prepared!
  Learn your material thoroughly
• A program of exercise is said to sharpen the mind
• Get a good night's sleep the night before the exam

• Approach the exam with confidence:
  View the exam as an opportunity to show how much you've studied and to receive a reward for the studying you've done
• Don't go to the exam with an empty stomach
  Fresh fruits and vegetables are often recommended to reduce stress.   Stressful foods can include processed foods, artificial sweeteners, carbonated soft drinks, chocolate, eggs, fried foods, junk foods, pork, red meat, sugar, white flour products, foods containing preservatives or heavy spices, and chips and similar snack foods
• Take a small snack, or some other nourishment
  to help take your mind off of your anxiety.  Avoid high sugar content (candy) which may aggravate your condition

• Allow yourself plenty of time,
  especially to do things you need to do before the test and still get there a little early
• Relax just before the exam
• Don't try to do a last minute review
  

During the test:

• Read the directions carefully
• Budget your test taking time
• Change positions to help you relax
  
• If you go blank, skip the question and go on
• If you're taking an essay test
  and you go blank on the whole test, pick a question and start writing. It may trigger the answer in your mind
  
• Don't panic
  when students start handing in their papers. There's no reward for being the first done
  

Check out local centers and resources in your school for assistance!