Sometimes the best way to prepare for the SAT is to look at as many different practice tests as possible. Thankfully, the College Board has been more than gracious enough to provide several practice tests. Just click on the link below, and check out all the different resources to help you!
The night before routine: eat plenty of carbs, sleep early, fall asleep listening to your favorite music
The day of routine: wake up early, eat a LARGE breakfast, dress comfortably (jammies are totally fine), make sure your cell phone is turned off upon walking into the testing room and placed in the provided plastic baggie to keep at the proctor's desk, take advantage of the provided breaks, etc.
DO THE BEST YOU CAN!! BEST OF LUCK TO ALL OF YOU!!