1) make flash cards for subjects based on content where you have to memorise things(question on one side and answer on the other), it took me one day per subject
2)print off mark schemes for essay based subjects (takes less than 1hr)
3)print off examples and try to write like them
4) for maths, do past papers
5) print off notes rather than making your own(takes too long) and use flash cards to memorise instead
You have plenty of time, I started revising a few weeks ago and I'm almost done with all my subjects, don't stress too much