Money, hard work, luck followed most likely by more money. Family financial support will be right in there.
The UK market is also very different to Australia. As you say, you will need to work your way up to the airlines, here you can get in with 300hrs straight on to a jet (i.e. 737) although I suspect that those days are numbered for the time being. Can also be a jet captain with only around 3-3500hrs if you're lucky and good enough.
If you have the right for an EU passport, then keep an eye on things in Europe and maybe try your luck some time. Big step.