Congrats on being able to graduate early! I'd partner up with someone else who might be doing the same thing. Mark up any study guides with a blue highlighter, as you're proven to remember things in blue (Or take notes in blue pen.) Colorful notes help too, and definitely do research on topics you're confused about. Study extra on math and make sure to know all the important formulas, most of math is memorizing formulas and plugging in numbers. Good luck!