Answer:
SAT, GPA, Personal Essay, Teacher Recommendations, Rigorous Courses, Supplemental, Interviews
SAT - this exam is made for someone how puts TIME and EFFORT into understanding their mistakes - and to not make the same ones again, someone may take 8 AP classes and have all A's but if you get a meager score on the SAT - it shows you did not take it seriously nor did you put time in.
GPA/ courses - take advanced classes in the subjects you are interested in!
Someone interested in STEM may take AP Physics, Chem or Bio someone who's interested in the humanities would take AP Lang & Lit, APUSH, AP Government or AP Spanish
Teacher Recommendations - teachers have seen you grow and develop, some you my make strong bonds with and this is your time to have actual proof from an adult of your accomplishments and work ethic.
Interviews - are you a person who is articulate, presentable or confident? colleges love that, go impress a college admissions officer through this.