I'm in the same boat as you man. I'm worried that I'll neglect my other maths subjects for just Chemistry.
In an attempt to get you somewhere with the question.
I'm doing all the question in my Heinemann book, and after every chapter, I summarise everything into a page on Onenote (or word). I also plan to work one or two lessons ahead in my class, that way, I'll know what my teacher is talking about and it also gives me a chance to either clear small doubts or deepen my understanding. O
f course silly mistakes are okay

We're only just starting, I was making a heap of stupid mistakes but I've noticed that they do gradually disappear. It may also be your concentration at that time too. Especially in this heat, I was making dumb errors so I just stopped. With regards to study guides, I've heard absolutely nothing but great stuff about Thushan's study guide. I preordered mine and he also gave me a preview of the guide during the meet on Thursday. I'd definitely say buy it!
I think many will agree that you should not base your study on "time" but rather content instead. Like I said before, I'm planning to work ahead by around 2 classes, for the holidays I plan to finish chapter 5 absolute tops..
To past students... Am I going about this wrong? Thanks

I've talked to a couple of past students about this though.