revision

hi sir ,
almost i covered up the ot notes and lectures and some bits of bpp text and some past paper from rev kit , but the thing is that i forgot what i studied first and when iam trying to ddo the past paper which i did before and again that too iam forgetting the things .
How should i do my revision phase should i do all questions from revision kit twice or thrice or should i focus on the latest past papers ? please give advice based on your experience.
Thank you