Well, I took a beginners yoga class not long ago. I used some of the moves the day before and the morning before my test. Also, I read parts of a book on managing stress and relaxation. One method they suggest is breathing exercises. During the test I would do breathing exercises right before each section. After going to the bathroom and eating a quick snack during my break, I usually have about 1 minute left. I would use that time to do my breathing exercises. It really helped me relax. You can find these books everywhere. Maybe give it a shot. Everyone is different and you may find yoga and breathing exercises pointless to help you relax. Try to find what works for you.