If you don't already have one, get a book of past HSC papers. Then do them. I've almost done a whole book for both 2 and 3 unit because we finished the courses ages ago. What you do is you try and do a whole exam... then when you get to a question you can't do, think about it first, then if you still can't do it, get out your notes and figure out how you should approach the question, then do it... that way you are actively engaging with the question instead of reading notes... because maths is practical and you have to use the skills rather than just regurgitate info practise is the best thing. I feel pretty confident about maths on Monday but only because I have worked my way through the past papers and it gets to the stage where you don't need your notes at all.
Another technique is to write all the formulas you need to know on flash cards. Write the formula on one side and what the formula is for on the other side and then quiz yourself... it's easier to learn and that way you are once again actively engaging with the info rather than just reading it over and over.
