perfect or close to prfect on the new 2016 sat.

Hey, i know that there is a lot of posts out there regarding this question, but i do not fully know my way around the forums so i was wondering if someone could just help me out. I did not understand how hard it was to actually make it to a top college until late junior year; i may have gotten a 4.0 last semester of junior year but by that time my gpa was already shot. I do not know exactly what my gpa is because i do not have my transcripts. All i know was is that the last time i saw my weighted gpa was mid junior year and my gpa was roughly 3.3. Anyways, i know that if i want a shot at a good uc my sat scores will have to be outstanding. I took the test in june, but i did not study at all and i know my scores are not good at all. I plan to take the sat in the beginning of my senior year and i was wondering if anyone knows of a strategy to a perfect. I understand that there is many resources available, but i do not have that much time so i need a way of studying that is not a waste of time, the perfect way. any tips? thank you.

practice tests are extremely helpful, make sure you know why you get things wrong, and see if there’s a specific type of question you always miss