I ended up with a 96 HSC mark for biz studies ..
I did a tonne of past papers and practice extended responses to the point where you could just tell yourself every single dot point from each topic and know what its about... so for the first two sections .. short answers and multiple choice the answers are pretty much straight from the syllabus you just need to know the exact term and your sweet.. for the report again the dot points outlining what you need to write about link directly to a certain part of a topic in a syllabus and to get the high marks you need to recommend your own reasoning and solutions to the businesses objectives with reasons why this is effective blah blah blah..
the extended response is based around knowing real business examples and showing your understanding of how the course is evident in real life... I did Harvey Norman and Qantas.. Qantas worked good because of current events in the news.. High marks come from information you find yourself - there are those study booklets you get for case studies but if you compile your own facts and dot points for businesses from the media or from financial reports your going to get some extra marks.
For writing the extended responses always start with a strong intro, something that can continue your argument/answer through the report and which ultimately answers the question, everything else just supports your answer you provide in the intro. A good guide to go by is SESL (State, explain, support and link) The band 6 responses have layers to their answers depending on the descriptive verb 'analyse' vs ' outline'. But the way to nail your business examples is by practice essays this way pretty much everything becomes so familiar you will just know how to link your businesses to any part of the syllabus.
The way i studied (don't know if it will be as effective to you as to me) is by talking to myself haha... I would talk myself the syllabus in a way I understand it, then close the book and say it again to myself as if i was teaching myself.. also teaching other people is an excellent way to learn and retain information.
Also because i found the business course had a lot of content i would read over the next lessons work through the text book either a week or so before just so when new things come up they don't sound so unfamiliar and class lessons become revision instead of learning new things.
All in all, i think i went well in business studies purely because i just loved the subject and enjoyed studying it and hence spent a lot of time just reading over it and put it first over all my subjects.
Don't forget about your assessment tasks either! They are just as important in getting a good HSC mark... so put a lot of effort into these if you have the time and you will be well on your way to achieving your ATAR.
Also hope you get state ranking for business! I wish i did D: