There are a few ways of doing this John B,
Firstly I am NOT a qualified accountant or expert, I can only speak from my own experience....
I kept my UK bank account open and I have tried bank transfers, HiFx and Currency Fair to transfer money. For me, over the past 5 years, I have found that Currency Fair is the best in terms of being quick, easy and better value (e.g. there are no hidden fees and the exchange rate is rather good).
If I were you, I would definitely discuss this with an accountant who knows about UK and Aussie tax laws before doing anything as there could well be tax implications and, who knows, you may be better leaving the money in the UK (depending on your personal circumstances)?
I am sure other people will give you the benefit of their experience too.
Good luck!