I think that from experience of doing Enhanced English at school (an accelerated program), the best advice would be to divide your three areas of study because each one really needs something different.
* learn your text inside and out.
* memorise important quotes that can be assigned to good themes.
* select themes that would be good to write about in SACS/Exams.
* analyse your points (hopefully they are valid) in relation to the question stimulus you are given, so that you are analysing rather than stating.
* develop a character/theme list where you have key points for each.
* Insight resources are the BEST. Purchase the book which only costs about $15 and gives you great advice on themes/character relationships, summaries, etc.
* Expand on vocabulary by establishing a vocab book. Every week, sit down and learn about 10 words you can apply to characters or use in your essay to embellish your work. You can learn these by writing down sentences and including one of those words in the sentence.
* Take not of any vocabulary your teacher may use when describing any ideas/concepts to you that you think will make your work stand out.
* Make sure (going back to knowing text) that you have read/watched your text at least 5 times, because this will ensure you know the text inside/out.
* PRACTICE - this is the hard bit; purchase an Insight yr 11/12 workbook that you can practice from and then emulate in your actually writing.
* Don't be too formulaic. Make your work more coherent by using joining terms like (nevertheless, additionally, similarly, etc).
* Have fun! English is an AMAZING subject because it really does involve an aspect of philosophy, which is where you really delve into the text and search for the interpretation of the text!!
* Read! Extra reading is really good, and you can do so from the newspaper, novels (JANE AUSTEN IS THE BEST), etc.
* Revise your structures regularly and try to write a text response or context every weekend and have your teacher correct them and give you feedback, so you know exactly what to do before a SAC.
Hope this helped, somewhat haha!