A good start would involve having a look at the syllabus document for the HSC course of your respective subjects. If I remember correctly, your subjects include English Advanced, Business Studies and Economics. Going through each of those subjects' syllabus document will result in a variety of benefits:
- English Advanced: You will be able to familiarise yourself with the main themes/ideas/issues raised within each module in advance.
- Business Studies: You will be able to understand the course structure as well as gain a general idea of the HSC topics.
- Economics: You will be able to gain a general idea of the HSC topics, some of which will expand on Preliminary concepts/topics.
Also, for English Advanced, in addition to the syllabus document, you should familiarise yourself with your prescribed texts (if known) as this can make analysing them a less demanding experience since you would have gained a good idea of what each of your prescribed texts covers (in terms of themes/ideas/issues raised by the respective modules) in advance. This will also allow you to develop and improve your ability to incorporate those different texts in your responses early on.
As mentioned above, you should be making study notes as you go (i.e. on a regular basis). It is also important to do so in a timely manner, so that you are able to manage your time effectively. Also, the type of notes you will make, such as handwritten vs typed/digital, is something to consider and is important to decide early on so that you don't face problems with respect to making notes later on.
I hope this helps!