As you say, its impossible to remember everything in the books! i have the first 8 exams passed now at 93% average. i started by re-writing the bristol notes, but after a few weeks I found this was taking far too long and when i got to the progress tests, the tests were much harder than was mentioned in the material. I then decided to only read through the material, only making notes on forumlas and ways how to do things (ie Grid Nav). Hit the QB hard, I found i learnt more from making mistakes after learning the basics in the material. If you get a question wrong in the QB always make sure you find out where and why you went wrong.
Take it easy