The best thing to do for maths is past papers. Just go through and try the questions without using any notes if you can. Then mark it yourself and make sure you understand what you did wrong if you didn't get the right answer. Gradually, you get to learn not only what you need to do, but the kind of questions which come up on the exam papers as you will find a lot of similarities. I find that doing past papers and going through them or doing questions from textbooks if you don't have access to past papers is the only way to effectively revise maths.
print out the specification with list of things in that unit (available online) and mark the topics you are least confident on. Always revise the things you are worst at. Also as mentioned above, going through past papers is probably the best way to revise overall.