Paying off your credit card balances and other debt can be daunting. Where should you start? How do you keep going? Make a list of all the debts you owe, says millennial money expert Stefanie O'Connell. Then start by paying off the debt with the smallest balance, using what's known as the snowball method—that is, starting off with the least intimidating debt and working your way up. In theory, you'd save more money by attacking the debt with the highest interest rate first. But thre's some evidence that you're more likely to stick to your debt repayment program using the snowball method.