Your taxable income must be at least the minimum income threshold. Your taxable income is shown on your Australian Taxation Office (ATO) Notice of Assessment.
You must have met the minimum income threshold for at least 3 income years.
Note that this is the taxable income, not the income before you add your expenses to your tax return. Taxable income is the income on which you actually pay tax.
So if your income is $60,000 and you have added expenses of $10000 on your tax return, your taxable income and your income for the purpose of subclass 191 is $50,000 which is under the required amount.