Math is Hard. It really, really is. There are thousands of tips on how to succeed in math class, here are some that I think are especially important.
Create Your Own Problems
Solving someone else's math problems demonstrates and ability to follow rules. Creating your own problems shows an understanding of the subject. It also forces creativity, an essential (and often overlooked) skill in mathematics.
Compare and contrast problems
Post game Analysis is so underrated. After doing 5 or 6 problems, ask yourself: which of these was the hardest? The easiest? What did all the problems have in common? What made them unique?
Don't Do Your Homework All at Once
If you decided to start training for a marathon, you wouldn't start by going outside and just running for four hours straight. Instead, you would run a little each day until you got into shape. Math is no different. Study or do homework for 20 minutes to half hour at a time. Then read a book, or make dinner, or call a friend... whatever. Just don't sit and do math for hours on end, it's counterproductive.
Do math in your downtime
Play math games; practice your arithmetic. I like factoring numbers in my head (the time on a digital clock, licence plates), it keeps me sharp, and it strengthens my ability to visualize difficult problems.
Read the Textbook
Yes, I know it's poorly written, all text books are. And no, you're not going to understand after one read through. But reading the text will at least familiarize yourself with the vocab and notation.
Later, when getting help (in class, from a tutor, from a friend) reflect on what you read. Why didn't you understand it when you read it? Do you understand it now? Over time you will learn to read math books.
The Internet is Awesome
Read the Wikipedia article on what ever it is you're studying. Look at the pictures. Google the subject, or watch lectures on YouTube. The more versions of a lesson you get, the more likely you are to gain insight.