This is a very difficult question, because everyone learns differently. Just remember that there are a lot of people in the same boat as you. It's pretty normal to not understand most of the stuff at this point.
Everyone will probably give you different advice, so you kind of have to decide what you think will work for you.
I'm no super star. I'm a 2L at a T2 school and I'm in the top 3rd. I used a lot of supplements in my second semester and I did a lot better than the first semester. It's possible that could be a result of a lot of things, but who knows.
1: Stay in the habit of reading the cases. This will help your performance on the final because your ability to analyze fact patterns and recognize rules will improve. Your finals probably won't directly test you about the cases, but you really need to be able to understand case law and analyze cases. Your legal research and writing throughout your career will depend on your ability to understand. However, a little help isn't really going to hurt you as long as your are trying to pay attention in class and doing your best to read most of the material.
2: Commercial outlines are fine, but I didn't like them as much as other supplements. I got outlines from other students at my school and they were pretty helpful.
3: Examples and explanations: Glannon has a great one for civil procedure. It really helped me to see the big picture. He takes you through the black letter law and some of the analysis, and then he has questions and detailed answers. That book was a life saver.
4: Law in a flash flash cards: a lot of people don't like these, but they really helped me. I didn't use them to help me memorize the law, I used them to help me learn to apply the law. My torts flash cards were basically full of hypos. So I had 600 little hypos and answers that applied the law to the hypos. For some reason that method just clicked for me. It helped me to learn to apply the law to different fact patters, which is what you'll do on most of your finals.
5: Legalines, Brief Books, High Court Case Summaries: These are books that are specifically "keyed" to your textbook and brief all of the cases in the book. These don't help me at all. Sometimes they are nice in a bind because they give you detailed briefs about cases. Also, many of them provide you with summaries of each chapter of your book. I borrowed a couple of these from a friend and they just made me lazy.
6: Crunch Time Series: I absolutely love these books. They are designed for finals prep and they are pretty short, but I loved the format. You get most of the legal rules, great flow charts, short answer and multiple choice questions, and then practice tests. This method of learning the same thing in 4 or 5 different ways was really good for me.
7: Practice Tests: These are crucial for most people. Your ability to respond to a test question quickly and efficiently without stressing out will go a long way to getting you extra points. Sometimes the difference between a B and an A is very small (when it comes to poits) so if you can quickly analyze issues and correctly state the rule and apply the law then you'll have an advantage.