Take your time on the easy ones!! Try to get as many right as possible. Don't rush the easy ones to make time for the hard ones youll only risk missing easy ones. However, know when to give up. You may not be able to do some problems. Problems shouldn't be difficult or take long. if this is the case, then you know you are doing something wrong. Also they don't dock you for guessing. So at the the end of each section if haven't finished some questions, just guess randomly and you're bound to get a few extra points.