I find BBC GCSE bitesize really useful. I either go through the revision, then teh activity and finally the test. At the end i will do the mock exam. Or i will transfer all the information onto a powerpoint - even though it takes a long time its worth it in the end because you can put some music on and flick through the powerpoint.
Additionally the AQA has lots of pastpapers on and it has exemplars at different grades so you can see what the difference between a C and a A is. It helps me because i know where other people have gone wrong and then will learn from their mistakes and the examiners comments.