The largest portion of a monthly budget will always go to fixed expenses (mortgage, rent, car promissory notes, public services, insurance, etc.) The 60-30-10 budget is a method for aggressive savers. With this budget, you don't focus on paying for living expenses first. Instead, you'll pay for yourself first by filling your savings with 60% of your income. In this method, 60% of your monthly income goes toward monthly living expenses.
These can be fixed costs, meaning that you pay exactly the same amount each month, for example, with your mortgage payments. Or they may be fluctuating, such as an electricity or telephone bill. If it's a real need, it's included in the 60% bucket. All the minimum monthly amounts you owe for credit card balances, car payments, and student loans should be included in this category.