First, keep only the credit cards you really need. If you already have credit cards or plan to apply for new ones, be sure to read the fine print on the agreement. Credit card companies will slip details into the agreement that aren't easily noticed. Read every word, and call customer service if something seems too vague.

Once you start using your cards, keep an eye on your interest rates. You might be paying a punitive rate if you've made late payments, or an inflated interest rate if you have cash advances from your credit card. Be clear about which types of charges incur interest rates above your base rate. And if you see that your interest rate has gone up without explanation, call your card company to ask why. They are usually very helpful in explaining charges, and will negotiate better terms with you if you stick to your guns (and possibly threaten to take your business to one of their competitors). You can also ask the card company if they will let you opt out of the higher interest rate, but this means that you can only pay off the balance of your card at the previous rate, not make new charges.

It should go without saying, but do pay your bills on time. Earlier is even better. Some cards start racking up late fees if you're even one day late with the payment ? ouch. Those fees are on the rise, too. It's best to pay credit card bills as soon as you get them.

Don't neglect your other bills, either. You don't want bruises on your credit score because you didn't pay your bills on time. Reports of default on your credit report can cause your credit card rates to rise. To be safe, check to see if you can set up automatic online payments for your bills. This will ensure that your payments are made in full, on time, every month. (Just be aware that fees sometimes apply for this method of payment.)

And if you're a good customer who makes timely payment, don't forget to call your credit card company to request better terms. Consider how much delinquent debt there is in America right now, thanks to the sub-prime mortgage crisis. Creditors are reporting record defaults. Your credit card issuer should value good customers. Let them know that you value good service. Competition is stiff in the credit card world, and they will want to keep your business. As long as your demands are reasonable, the card companies should agree.

If 2007 took a toll on your finances, you're not alone. But with a fresh perspective and a few new habits, you can shine up your credit in the new year.