If you struggle with impulse spending, this cash-only challenge is for you. First, decide how much money you need to budget for your expenses, such as groceries, takeout, shopping, etc. Then, every month, withdraw only that amount in cash and put it in envelopes labeled with each category (i.e. a budget of $200 in your "groceries" envelope). The goal is to only use that cash for each category, so, for example, once your grocery cash is gone, you can't spend any more for the rest of the month.