My strategy is:

one account for fixed bills, mortgage etc.

one account for everyday spending (groceries and fuel, essentially - only sensible essential stuff)

another account or credit card for the silly stuff.

Close the silly stuff card before doing the home loan application and they don’t see ANY of that spending at all. You don’t have to give them statements for closed accounts.

When I was a lender we reviewed 3 months prior and checked for:

expenses matched declared expenses

no evidence of undeclared direct debits or loans or credit cards

no evidence of familial loans

no evidence of gambling or money laundering

no evidence of undisclosed private school fees or private health insurance (these were big ones that caught people out)

strata fees and investment property expenses (if held) match disclosed expenses