Answer:
Hmmm.... well for one thing I would at least review a few things, just so you can feel a bit more confident in your work, then if that doesn't work you can review more or get your mind off stuff by going somewhere fun. SLEEP It's kinda hard yes but still staying up all night studying and worrying isn't going to do anything but make you sloppy. Make sure you are well fed before said test. Mainly just don't strain yourself too much because like I said before it'll make it harder in class.
I'm sure you've heard this before but yeah it works if you really take it to heart
I hope this helps! <3 even a little bit?