Technically, you're not supposed to do ANYTHING related to the test the day before the exam. That would be tomorrow for you. However, if you're like me, you just can't keep your hands off doing old questions and stuff like that. So, since I could not resist, the day before my exam, I just READ over my notes. That's it. I did it up until lunch and then I just stopped. I wanted to give my brain a rest. This is important. In fact, the few days leading up to the exam, I realized that I either knew it or I didn't. The few days leading up were not the time for me to be learning new facts. It was 100% review. The week before this though, I did do all of Chad's again and poked around Destroyer.
With this said, do what is comfortable to you. Go in there with a good mindset. That's almost just as important as knowing the material. If you freak out, it WILL affect your score. I was able to go in there with a calm and collected mentality and just start taking it. Sure I was nervous but not to the point that my mind didn't function. Once the test begins, the world around you fades away and you are only focused on the single question at hand.
Oh, and when one section ends, FORGET ABOUT IT. That means that when the sciences are over, FORGET IT and focus ONLY on PAT (after all, you cannot go back and chance an answer in GC when you are in the middle of hole punching so what's the point of agonizing over a question from another section). When PAT is over, do the same thing. You need to completely remove any thoughts that you had about previous sections from your head before you move on to the next otherwise it will distract you.
Good luck.