Before you can get a divorce you need to have been separated for 12 months. Family lawyers will tell you that this does not have to be in different accommodation; you can be separated while still living in the same home if moving would cause financial difficulties. However, one way to prove to the court that you are separated is to have separate bank accounts.
So on the day you separate, you should set up an account in a bank or other financial institution in your name only. Even if you have no money, you can often simply set up the account with a zero deposit or a low deposit of one dollar. After that, if you are on a government pension or benefit, you can to go to Centrelink and have them pay the money into your new account.