Self-employed individuals are responsible for paying their own taxes. This means that, when you are self-employed, you are entitled to a self-employment tax.
You need to set aside money throughout the year to pay your taxes. Also, you will need to file a tax return each year.
You are responsible for making sure you pay the right amount of tax, according to self-employed tax return Australia. You can also check out Maximise Your Returns: Tax Planning Tips for Small Businesses.