Ok, so I’ve wanted to do this for aaaages (well, ever since I went to Byron and learnt it was the most easterly point on the Australian mainland), and here is one possible way of doing it:

Stay in Byron overnight – e.g. camping would be fun. Then get up to see the sunrise, have breakky on the beach… then get a flight from Ballina to Sydney, then Sydney to Perth… in time to have dinner and a bonfire on the beach while watching the sunset :)

And then figure out what to do in Perth.

(JK)