Get off answerbag and start studying! :D In many cases the best way to study for science is to not only review notes, but do problems. Your textbook probably has review problems, so do them and then check your answers after. Review your old homeworks and notes.

Don't be nervous. It's better than being over-confident, but it's still not the best way to enter an exam. You need to remember three little things: 1. You've studied for this exam. You've done the questions, and figured out the answers. You've seen the course material and trial exams. THERE IS NOTHING ON THIS EXAM THAT YOU CANNOT DO. 2. You are an individual in a group. Exams are designed to test a range of abilities, and not everyone is supposed to get 100% score. Some will do better, some will do worse. You will do better because you are actively doing something about it. YOU ARE NOT IN COMPETITION WITH THE OTHER STUDENTS. 3. An examination is just that, a procedure for testing. If you blow it, whatever. It you fluke it, congrats. Either way studies show that you are more than likely going to forget 90% of what you've learnt. So long as you do your best and train your brain to be able to learn and adapt to future situations, you have progressed. IT'S NOT THE PENULTIMATE EXPERIENCE OF YOUR LIFE (that'll probably come later). Study hard, get a good night's sleep before, wake up bright and refreshed, eat plenty of vegetables and cereals before hand and drink plenty of water. Steer clear of caffeine, sugary or fatty foods, food colourings or MSG and for goodness' sake go to the toilet BEFORE the exam.