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When it comes to credit cards, you can be your own consumer advocate . . . or your own worst enemy. And these days, this lesson couldn't be more important.

According to TransUnion, one of the major credit-reporting bureaus, the number of new credit accounts grew by 14% in 2011, including subprime credit.

While I'm glad that subprime consumers are able to get back into mainstream credit, be careful. You're likely to get a high interest rate, so don't carry a balance. And I hate to sound skeptical, but even though the Credit CARD Act is in place, there are still plenty of ways for banks to take advantage of consumers.

Since so many people seem to be rediscovering credit cards, it's a good time to look at ways you can protect not only your credit but your hard-earned cash as well.

1. Speak up if you're unhappy

For this to work, you need to stay under your credit card limit and pay your bills on time. Then you'll have leverage when something unpleasant -- like an interest rate increase -- happens. If you get whacked with a high rate and you're an exemplary cardholder, call the issuer and state your case.

Likewise, if your annual fee goes up, call and ask them to waive it. Tell them you've been an outstanding customer. You've got offers from other card issuers who are happy to have your business.

See how this is done? You can always be an advocate for yourself, but this strategy works best if you're a top-notch customer. Speak up and you might be able to keep more of your cash where it belongs: in your pocket.

2. Keep tabs on your credit history

Every year, you can get your free credit report from each of the major credit bureaus -- Equifax, TransUnion and Experian -- on AnnualCreditReport.com.

You want to review the report and look for errors or any signs of fraud. An error can really bring down your credit score, and that will cost you when you apply for a credit card or a mortgage. This is a simple but very effective way to protect yourself when it comes to your credit life. Put it on your calendar, and every four months get a report from one of the bureaus.

To keep tabs on your credit throughout the year, use Credit.com's Credit Report Card for an easy-to-understand overview of your credit standing. (Take this free MSN Money quiz to get a credit score estimate.)

3. Get your credit score

A FICO score is what most lenders use to gauge your creditworthiness, so that's the score you want to look at. You can get your FICO score for $19.95, or you can use other credit-score-monitoring products, but make sure they include a FICO score.

Credit scores go up and down constantly, so keep in mind that you're getting a measure of what your score is at that particular time. Even so, I think it's vital to check your score from time to time. This gives you an idea of your credit range so you know what types of credit cards you should apply for. Your score will get dinged if you repeatedly apply for cards that you can't possibly qualify for.

4. Be aware of the consumer protections your card provides

Many credit cards, especially those in the elite group, like Chase Sapphire Preferred, offer purchase protection and extended warranties. Purchase protection can be a real benefit if your merchandise gets stolen or accidentally damaged.

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Extended warranties on credit cards extend the manufacturer's warranty, which varies by card. It's not unusual for people to buy extended warranties when they already have them via their credit cards. Some credit cards even still offer price protection, but this isn't as common as it used to be.

How do you know what protections you have? They will be listed in the disclosure statements. If you didn't keep them when they arrived in the mail with your card, get online and read the fine print. If you can't find the information about these benefits, call your card issuer and ask.

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