Yes, spam practise papers, maybe start by a couple trial papers, and pick out any topics you're rusty with to look over again, refine, then spam out more trial papers. always go under timed conditions, and if you don't have enough time adjust the time according to marks (like minutes per mark). always mark your papers, and bookmark all lost marks which weren't silly mistakes (like a knowledge gap). resist looking at the solutions and try solve it even like after time's up, because its really likely there'll be questions you have no choice but to skip in the hsc. save the hsc past papers till the end when you're really confident.