The best advice for SOR is to read a get a hold on the syllabus. Once you understand the syllabus then you can get rid of all of the extra information teachers yap about but will never assess you on. You can find the syllabus on the Board of Studies website. Read through your textbook and class notes and make up some of your own revision notes under the dotpoints of the syllabus-these are the only things they can assess you on. Find a format that works for you. SOR is an easy course, and a fairly concise one if you break it down and get rid of all the extra stuff. If you need help with formatting, there are a number of HSC study notes in the resources section. Using someone else's notes won't necessarily help you, as they are made specifically by the person and some things can be a)by passed b) abbreviated or c) written in in different contexts. Make your own, it's great practice for senior school and you will understand the course in the best way possible for you. Also, if you're struggling with it, dedicate some extra time to it. An hour or so on the weekends or one night a week for pure SOR study (including making summary notes of the course)
This is just what works for me, hope it may help you.