So I was thinking of possibly travelling the east coast of Australia from Melbourne through the main cities and coasts such as Sydney and Byron Bay, all the way to Cairns over a couple of months. I know it will vary from person to person depending on what you want to do, but can anyone advise me on roughly how much to take with me if I want to do the general touristy things but I don't mind staying in cheap hostels? Just if someone has done a similar sort of trip, can you please give me some idea of how much I would need? I'd probably go around January. Thanks!
I generally give a ballpark estimate for a comfortable average daily budget of AUD $80/day. That amount of money allows you to stay in dorm rooms in decent quality hostels, buy supermarket food to cook your own meals, travel from place to place by public transport (staying in each location for about a week), and do some incidental activities (thing platypus spotting rather than skydiving).
You can live slightly more frugally if you try hard. On the other hand, you can spend 2-3 times as much without any effort, particularly if you go out regularly or do lots of activities. In the end, it all depends on your personal travel style. Watch your expenses as you go along.
I'd recommend taking it slow with going up the coast, since the north will be enduring the wet season until March-ish (noticeable from around Brisbane) . Not that the south will be much better, what with the yearly bush fires in January... (Those you can generally avoid without too much trouble, though; just keep yourself informed of their existence, and plan to stay away from them.)