Also, it's good to have a study procedure. A procedure is a set of instructions you follow to get a result. I didn't understand what studying meant growing up; I pretty much faked it all the way into college. To me, studying means 2 things:
1. Comprehension
2. Memorization
They are two separate things. You can memorize something, but not understand it. And you can understand it, but not remember it. Putting them both together is where the real power is - you understand it & you remember it. The memorization technique I linked to in the post above helps with remembering things. This is especially useful for stuff like math class (formulas) and history class (names, dates, events).
My comprehension workflow has evolved over the years. Memorization is easy; you just put in the time using the "how to memorize anything" procedure & voila, you have it memorized. But being able to
use that data is where the key lies, especially in math classes. My current comprehension technique goes something like this:
1. Create a list of study topics by scanning the section of the textbook you're working on & picking out the major topics. So that might be what sin, tan, and cos mean.
2. In the order presented in the textbook, take each topic & draw a mindmap for it with all of the information it gives you in the book. So for sin, that might be what sin means, a little drawing of a triangle, and an example formula. Sketching it out in a little bubble-tree like this helps me to get involved in working things out in my head, instead of just staring at the textbook & trying to piece it together mentally.
3. This is the part where you figure things out. Having it out in a mindmap format should help you see all the pieces relevant to that one main piece of information.
4. Once you've got it figured out, write out notes into short sentences.
5. Use the stacking memorization technique to burn it into your brain.
When you go to do homework or take a test, you can pull up that information thanks to the memorization technique, and since you've figured out how it works through mindmapping, it will start coming back to you. If all you do is memorize it & never figure out how it works, then it will be equally useless if it's a formula you actually have to apply to a problem.
Also, there are a lot of good resources available. One of the best is Math Tutor DVD, which does online training videos. It's $200 a year for a subscription. If that sounds like a lot, remember what you spent on your math textbook, and remember that a subscription will cover two full semesters. Here's a link:
http://www.mathtutordvd.com/
Tutors can also help, if you can find/afford a good one. And Youtube. And googling. My problem with most textbooks is that they're terrible at explaining how formulas work; I always hated math growing up and didn't realize until later that most of them are just poorly-written. Not enough examples, no explanation of different iterations, you're just expected to figure things out on your own. The point of learning, to me, is to stand on the shoulders of giants - i.e., quickly learn & memorize what other people have already put in the effort into figuring out, so that I can benefit from that existing knowledge. It's like experimenting with different ingredients to find a pancake recipe...why not just give you the recipe, explain how it works (ex. baking soda rises), and then get great results? But most math books are not well-written and make you re-invent the wheel every time you go to study. Some people have a knack for it, but I sure don't!