How do you guys lower stress right before a test?

So, I have a Calc II exam tomorrow. My first, and I don't think I'd be so worried, except, consensus from past students and how his class has been is making it feel like the test is absolutely going to suck. (50 minutes to take it, 5-6 problems, he says the questions can just pop out of his head, so I don't even know if doing book questions is going to help; oh, and he's hardcore Russian)

I've studied quite a bit and I know how to do the types of problems he wants us to do, but I'm still stressed. And being stressed probably won't help me do better.

So, before a big test, how do you all prepare yourselves for it and lower your stress before the big day?