Lachlan, you can try Airservices Australia's website -
https://www.airservicesaustralia.com...tc/default.asp
It contains many information on becoming an Air Traffic Controller. The basic requirement is completed Year 12 with passes in English, Maths, Science (preferably Physics) or a tertiary education qualification or a commercial or private pilot licence.
You get pick your preference of Enroute, Terminal or Tower controller but it is ultimately up to where Airservices Australia assigns you.