Whether you consider your work to be “commercial” or not, operating within the “Sub 2 kg drones for business use – excluded category” provides you with a solid framework for safe flying when you do not have a Remote Pilot Licence (RePL).
The Drone Safety Rules page of the CASA website summarises the Do’s and Don’ts of flying. You should be familiar with the Civil Aviation Regulations Part 101and the Advisory Circulation AC 101-01 v3.0 as it is your responsibility to make sure you are following all the rules that apply to your use of the RPA you are piloting.
Checking local laws is important as the rules can differ on whether you can fly in national parks between states and on the distance you need to keep from marine mammals. The Flying in Public Spaces page by CASA has links and information on this. It also has a link to an RPA being taken out by a large bird of prey (if you didn’t know, they are not that keen on sharing airspace) – it is definitely worth the watch!