Read over the stuff you're covering in class beforehand. Don't go hard out and learn 2 weeks ahead of everyone else, just make sure you understand the basics before you do it in class.
Don't do the homework if you feel you understand something sufficiently (I never did any calculus homework and minimal locus homework) - You don't have enough time to be doing stuff you don't need to be doing. However, if you don't get a concept, keep doing more problems until you get it.
If you're struggling on a question (10-15 minutes on the one question), skip it and ask for help in class the next day. Again, not enough time.
In regards to actually doing exams, do as many past papers as you can. BUT MAKE SURE YOU UNDERSTAND EVERYTHING BEFOREHAND. There's no point practising exam technique if you don't understand what you're being assessed on.
Personally, I find watching lecture style videos helpful with regards to understand concepts - I use Khan Academy (
www.khanacademy.org) and
http://www.slideshare.net/nsimmons which is presentations uploaded by a 4 unit teacher from baulko. However, you might prefer just reading the textbook or your own notes, it's up to you.
