What I did was trying to get ahead of the class in terms of theory and doing practice questions as soon as I learnt something new - I thought it was rather effective for me.
Also, I think I had mid-years around the middle of the term so I tried to practice papers every now and then and handing them to my teachers to mark. I think this would be pretty good since your teachers are the ones marking your mid-year exams so you'll want to know how their marking is like