Raise your hand if you're taking the SAT tomorrow?
Be sure to get a good night's sleep tonight! Don't stay up late going over questions you already know. If you must, do a few practice problems, but then set the materials aside. Enjoy a healthy dinner, de-stress as you normally would (take an exercise class, watch a few episodes of your favorite show, call your BFF), and then get to bed at a reasonable hour. Trust us, you do not want to be tired or overly stressed for test day!
You're going to do a great job!