Well, I've took it pretty easy after English Lit (AQA A) and ICT (OCR A) on Tuesday. In fact I'm here right now, because I can't bare to do any more revision tonight.
The best way to revise is past papers, there is no doubt about it. I was reading my revision guide for Geography, I could recite facts etc, but I sat down to do my first past paper today (I have been putting it off) and realised the questions are very simple, yet I couldn't answer them. By trail and error and reading the mark schemes I could tell exactly where I could score marks. People don't realise explaining a point often gets you an extra mark, always EXPAIN, EXPAIN, EXPLAIN!
Anyone after past papers check the AQA website, even if AQA is not your course. I do OCR ICT, but I used AQA past papers, which covered the style of questions that come up (sounds odd, but OCR have totally changed the specification, old OCR past papers were pretty much useless).
Use AQA for Maths, I do the Edexcel course, and there is little difference in the specification. I find by looking over mark schemes I can pick up a grade by looking what examiners look for when marking your paper (simple stuff like rounding figures correctly or using the correct unit in Physics will get you a mark).