You should be able to document your income, expenses, and (hopefully) savings every month. If your income minus expenses is a positive number, you can relax a little. You still may want to work on your budget so you can save more for an emergency or retirement. If that number comes out negative, you could be in big trouble. Spending more money than you make means you must rely on credit. In turn, this means you are setting yourself up for more trouble because those credit card payments will get higher every month.
When you start working with making a household budget it is extremely important to track your spending and all your expense both on a weekly and monthly basis. Many people dread tracking their expenses and recording every receipt but this is by far the best way to gain control over your spending. There is always a huge gap between what people think they spend and what they actually spend each month. So, tracking your spending is the only way to establish a working budget.