Since professors won't tell you how to do well on your exams, I will. Because you cover so much material, you need to make an outline for each class. You can do this alone, assuming you have about an extra thousand years to kill. An easier way is for your study group to divide up the classes, with each person outlining one class. This differs from the prior approach in that it is humanly possible. You are likely, however, to open up your study group's contracts outline the night before the exam and find a sentence like this: "An offer is the manifestation of gooberness to enter into a something or other (I didn't catch what the professor said here) so made as to justify another person in understanding that [illegible] is invited and will gyre and gimble in the wabe. Or something like that." You then realize that the classmate who wrote this dropped out six weeks ago and is inaccessible by telephone, and you run around the room screaming like the lunatic that you are. So it's really better just to buy the commercial outline and forget it.
Then, memorize the outline. As you pour it in the top of your head, most of it will run out your ears. Keep scooping up the stuff that runs out your ears and pour it back into the top of your head. Eventually, a little of it will begin to stick. You should also use acronyms, or "pneumatic devices," to help you memorize. For example, the prima facie case of a tort action for negligence has several elements: an Act or omission, a Duty, a Breach, Actual cause, Proximate cause, and Damages. The first letters of these elements are A, D, B, A, P, and D. Now, think of a sentence using words beginning with those letters. For example, Ann Drop-kicked Bunnies And Pretty Duckies. See? You will never forget the elements of negligence again. You can use this technique to remember everything you learn in law school. Using this method, one student was able to reduce his entire civil procedure outline to one word, and finally, to one letter. Then he forgot the letter.
Next, get some of the professor's old exams from the library and try to answer them. As you read them, note that you don't have the foggiest idea what they are asking. You can't even tell what the subject matter of the class was. Put the exams away. This year's test will probably be easier.