While a week and a half may not be a substantial amount of time, you can still cover a lot during that time. You seem to have a good understanding of the essential study requirements to perform well in each of your subjects, and that is a good start. In your particular case, there are two main elements that you should focus on in preparing for your trial exams.
First, you should have and follow a schedule that details the amount of time that you would allocate towards each of your subjects as well as the order in which you will prepare. Here, you may wish to consider subject difficulty. For example, it would be good to allocate additional study time towards a subject that you may be struggling with/where your level of performance is low(er), and perhaps allocate slightly less study time towards a subject that you find easier/perform well in.
Second, you must try your best not to procrastinate. Every study opportunity that you get counts, and procrastinating will reduce the already limited amount of time that you have to prepare. As such, you should avoid any form of procrastination that may currently be affecting your ability to study hard. You should also always remind yourself of your academic goals and the importance of achieving them, as well as the fact that your HSC will be over in a few months, after which you will have plenty of time to have fun.
I hope this helps!
