Hello! I'm new to flying solo so please bear with me if this is a stupid question.
I provide barista services wherein I operate a coffee machine, serve people, take money and sometimes drive the van.
With one client, I'm being paid a percentage of the day's takings as opposed to a set hourly rate or pre-arranged sum. In this case, I work three hours and in that three hours I make x amount of dollars and whatever that may be I get 15% of it. Of that 15%, I have to pay my tax and maybe super.
I don't pay any expenses or insurances or anything -that's taken care of. All I do is show up (with a professional attitude of course

) and do my thing. The principal puts my ABN number against the cut he gives me. There is no contract in place.
Thing is, how do I work this? When I do the sums I'm a bit lost.
Thanks.