It's about finding what works for you. Personally, I only did VCAA 2006+ (and some company exams in Unit 3, which I then abandoned later in the year). It rather worked for me to do notes-study and asking and answering questions about the content (a primitive version of
Biology Theory Revision Questions). As Bruzzix said, you can make your own questions (hopefully better than those in the link), both theory related and application - really helpful.
If redoing it, I'd probably mix these theory-revision methods with more company exams, but in a time-saving way. I'd go through each question really fast in your head. Map out quickly how you’d answer it; if you’re confident that you know it, check the answers and move on to the next one. When you hit one you’re not so sure of, circle it and come back later to do it properly. Make sure you're brutally honest with yourself! This method means that you might get through a 2-hr trial in 45 min, and only physically answer five questions, the five that you really needed practice on. (This is the method I used for HHD, and it works like a charm).
Don't know about other subjects