Dedicate 2 months to only studying the DAT, don't half ass it or you will get half ass scores. Cliffs AP Bio, CHADS DAT vids, DAT destroyer, Math Destroyer, Kaplan book (optional), DAT sim program (I used Achiever)
Achiever PAT is abnormally hard IMO, as is their whole test. If I remember correctly their graphics are also a bit off making angle almost impossible. Achiever does have nice 3D model explanations for the Key-Hole and Side Determinations though.