Try to learn it from the book, but look or ask online for explanations to anything you don't understand. The Bristol brush up course was good for filling in any gaps.
In addition, hope you have good luck with the questions on the day because you can't possibly know it all. Ask most airline pilots to explain gyros and they'll go green. You have to grasp the concepts and know the detail in the exams, then you'll readily forget the detail as your brain steadily decays!
IMHO, of course...
