I did Religion and Society 3/4 last year and I found the most effective way to study was to write crap loads of essays. Like all the time and getting teacher to go through them with me, picking out words she didn't think were necessary and/or one's I should add instead, etc.
For english I employ the "sourcing" strategy. Basically I'm not too good in english, however I get decent marks because I'm always reading other people's essays to gather ideas and most importantly new words, unique phrases, etc (through brainstorming, discussions, always writing down pretty much everything the teacher says). I guess I'm lucky like that because my english teacher, the way she answers people's questions is by dictating or making up an essay on the spot, lol.
So, like R.E, just practising writing essays to improve your writing skills, and your ability to "read between the lines".
For maths and physics (and probably the other sciences), the only way to study - I reckon - Is to (obviously after fully understanding the concept and why things work that way) do heeeeaps of questions. Usually teacher says like do Q 1, 3 LHS only, etc.... I just do them all. Even though it gets boring because your doing the same thing over and over, eventually it'll stick in your head, and you'll be able to do it without thinking too hard.
I personally don't like writing notes. That being said however, in my physics book, on the last pages I use the back pages sort of like a cheat sheet I guess... I write down formulas, questions to look out for, etc.
And the most important thing: Maintain a regular study routine. It's like such a cliche because EVERYONE says this, but seriously it probably is the best way to do good in year 12.