Lovetorun and others. There is not a lot you can do to prepare. Just be willing to work and study flat out. It will be nothing like any other course you have done before.
You could browse Skybrary (Google will find it). It is a good source of aviation material. The ATC content may give you some insight although not all is applicable to Australia. If you do use it, don't ever say "Skybrary said" to an instructor.