I did a bit of Geography (edexcel b) over February half term, and I'm going to start to tackle my weakest subjects this week. I made a timetable and will hopefully have the willpower to stick to it.
I really REALLY recommend downloading and printing exam specifications, they're like a checklist of everything you need to know in the exam. This saves you from writing useless stuff in your notes from textbooks that you don't need to know, and you can really make sure you know everything you need to for the exam.