Credit cards work best when you are a disciplined spender. Have only one or two cards in your wallet and make sure they match your spending habits. And make sure you can pay off the balance in full (or at the very least make the minimum payment) every month, so you don’t have to pay hefty interest on your unpaid balance. This can result in costly fees or in having points knocked off your credit score. With a bit of self-control, credit cards become helpful and convenient financial tools that can make everyday purchases easy.