Fellow Ancient Historian!
I did my ancient half-yearly today and it wasn't so bad- I obliterated it actually. For the HSC (trials) you only really need to know the Delian League/ Athenian Empire part or the Persian Wars part as you get to choose.
For the Persian Wars, you don't need to memorise exactly what happened in the battles- just enough to distinguish one from the other. Any question about the battles will usually get you to 'assess' and 'evaluate' rather than describe so look at the battle in the context of the whole war effort.
The Delian League is a bit harder to memorise but learning this will provide you with a lot to write about come exam-25-mark-question-time, because it may ask you to 'describe'- basically you're just retelling what you've learnt word for word.
In terms of learning the stuff- for me I put everything in one big sequence so i can picture the events; you have to fully understand what happens to keep the info in the long term. For example, if learning all the places is difficult, plot them on a geography/topography map so you know why Mardonius chose Plataea for example, or why Delos was chosen as the Delian League's treasury.
It's good to get some past HSC questions so you know what you're dealing with, and use 'Notes from the Marking Centre' and the 'Draft Performance Bands' so you know exactly what the markers expect of you.
I- feel smart. :mad1: