I used a lot of different sources but did not finish each one by itself. For example I bought the kaplan big book but only read two sections from the book. I would do a chapter of Cliffs Ap biology and then check to see what the kaplan big book had on that certain bio subject ( so I combined the two books' info in a way ), I did the same thing for the physics section and since I knew I was weak in physics I went and purchased another resource Princetons OAT book which is a book just on physics ( highly recommend it, was awesome). After reading all these physics sections I then watched chads videos just to make sure I covered everything that he spoke about. It did help. I also watched Chads videos for gen chem and organic chemistry and AFTER i finished all his quizzes post video I went and did every question in the OAT destroyer book. SO, I dedicated 1.5 months to reviewing material, and 1.5 months to doing OAT destroyer and working on the sections I didn't think I would be good at like biology ( just because there is SO MUCH information) and physics.
This is the method I found that worked best for me and was accepted to my top choice.
I should also add that I did purchase OAT achiever and attempted to do 2 practice exams. My scores were terrible but it's good to have an idea of how the computer software runs and I think these programs did stimulate the actual exam. The CONTENT however, was not a good representation of the actual exam. The actual OAT was wayyyyy easier than these practice exams.
