Constitutional law books, understanding the Constitution, law school study aids,con law outlines, exams, Con Law Examples and Explanations.
For constitution study aids I recommend the Examples and Explanations and Crunch Time. There is a list of law outlines below that you can go over but you really need to develop your own outline. Use these only as a guide and to be sure you have not missed anything. The law school essay is where you need to pick out and discuss the issues. Your law professor has a grading sheet and has assigned a value to each issue. The key is to recognize and then discuss each constitutional issue in the short amount of time allotted. The best way is to go over old exams and do a timed practice.