I NEED HELP!!! CLUELESS SAT TAKER

I BSed a full practice test really quick just to see the range i would be at if i didnt really try so i would know how hard i actually needed to study.
i got
Reading: 520
Writing: 490
Math: 350
Multiple Choice: 43
Essay: 10
how do i calculate the score out of 2400??
any tips for studying? How good did i actually do in the Pre Test. Any tips will help. Im taking the test in 3 weeks.