This is the place to start. See where any gaps are in plenty of time. Then follow with some or all of the suggestions below:
Reading through notes
This is NOT a revision technique. It just makes you sleepy, and panic since you aren’t learning anything. If you want to learn from your notes, DO something with them!
If you have an emagazine or emagplus subscription, you can read my article on revising for English exams in emagazine 40 (Apr 2008)