Oh goodness! I hope I'm not going to sound too harsh here.....I applaud your efforts, but I can't help but wonder why your teacher isn't doing this with you. Not just a little bit here and there but going over it until it is understood. It's part of the 'job' surely.
Now it sounds like I'm critising the teacher. I don't mean to, but it just sounds strange to me.
If you were learning a foreign language and the exam included both written and spoken skills, would you expect the language teacher to leave you to learn how to write this language whilst they just concentrated on the aural side?
I suppose I'm just wondering why this is being left to you and some of the other posters.
My students learn the theory grades alongside the practical. They don't usually take all the theory exams though. We do Grade 1 theory, Grade 1 practical, Grade 2 practical (but have worked through the grade 2 theory syllabus). Then Grade 3 theory, Grade 3 practical. The theory side is often not very popular with the younger ones, but that doesn't excuse me from the task.
When the get to grade 5 practical they have already taken the Grade 5 theory. Often they drop the theory after this giving me the extra time to concentrate on the practical side for the rest of the grades.
If I suggested that my students worked through the theory on their own, they'd look at me as if I had 2 heads.