Making sure you work out exam timing is very important before your trials. Each HSC paper has suggested time allocations on the cover sheet and they will give you a rough guide as to how much time to spend on each section. Spending an extra 5 min on one section may actually prove detrimental to the remaining responses. Work out timing ahead of the exam and after writing time put down starting time for each section on the paper before you begin. Remember bigger mark questions require more time. 3 hour paper = 180 minutes - which works out to roughly 1.8sec per mark - now do the maths…
Also if you’re not much of a writer get some practice in beforehand - you need to be able to produce quality under pressure and a dress rehearsal is really advantageous!