I think that in order to give your self a chance to score well, you should not study on Friday before the test. Just chill out on friday, do something you haven't done in a couple of weeks and get a good nights sleep. Whatever you might learn while cramming on friday night is no worth getting two hours of sleep before the test an be extra anxious during the test.
The main thing is to minimize the amount of stress you have before and during the test. Doesn't matter how prepared you are for the test and how many times you have scored 40's in practice, you will be nervous during friday night and all day saturday.
Just try to make it through the day without just cracking to the pressure and Sunday will be a whole new day (that is for those of you that are taking the test on saturday).
dmitri