Get the latest local business news delivered FREE to your inbox weekly.

Portrait of a happy Latin American woman at home checking letters in the mail and smiling - domestic life concepts

You might know the basics of how credit cards work and even have several in your wallet already. But as you tear open the envelope on a brand-new card and activate it, you encounter a minefield of potential mistakes that could prevent you from getting the most out of it.

Of course, some basics apply to all credit cards. A prime example: Avoid interest by paying your balance in full every month if you can.

But optimizing your new credit card also means avoiding gotchas and not missing out on benefits. Here are common mistakes people make after getting a new credit card.

If your new rewards card offers a sign-up bonus for new cardholders, it usually comes with strings attached. You might have to spend, say, $1,000 on the card in the first three months or you won’t get that $200 bonus.

To hit such a minimum spending requirement quickly, you'll want to charge everything you can to the new card, but without going beyond your normal budget to do so.

Be aware that returns and refunds usually don’t count toward your spending requirement.

Similarly, the clock is ticking on taking advantage of 0%-interest introductory offers. Make note of the deadline.

Aside from activation, other tasks come along with a new card. For example:

One task you can skip? Signing the back of your new card. Feel free, but it’s rarely required anymore.

If your rewards credit card offers extra points or cash back for purchases at supermarkets, for example, you might be bummed to discover your Costco purchases didn’t qualify. It sounds like a catch, but it’s typical with credit card categories because merchants are identified by their merchant category code, or MCC. With many cards, Costco is considered a warehouse club, not a supermarket.

If you have a subscription that falls into a bonus category, like streaming services, make sure to log into those accounts and switch your payment method to the new card.

More generally, develop a system for remembering bonus categories on the new card. That could meaning affixing reminder notes to the physical card or jotting down categories in a file on your smartphone.

It’s worth taking the time to read your benefits guide at least once to get familiar with card perks.

For example, you probably know if an airline-branded credit card offers frequent flyer miles for your spending, but many offer free checked bags, too. At a typical cost of $30 a pop each way for checking a bag, skipping that perk would cost an extra $120 round trip for you and a traveling companion.

Especially on travel credit cards, look for travel credits, airport lounge access and free hotel nights.

Minor perks are worth knowing, too. Your card might offer cell phone insurance, rental car insurance, price protection, extended warranty or free FICO credit scores.

The rewards you earn for credit card spending are only half the value equation.

Especially when earning points instead of cash back, consider what points are worth when you cash them in. For most cards, aim for a penny per point in redemption value. In some cases, point values for merchandise, gift cards and "pay with points" (like at Amazon) aren’t great values, offering less than 1 cent per point.

Nerdy tip: With travel credit cards, consider transferring points or miles to other loyalty programs. It’s how a lot of credit card enthusiasts get outsized value for their points or miles.

Many large credit card issuers offer card-linked discounts or extra rewards at certain online retailers.

They offer web-based portals and deals that allow you to stack savings or points on top of your card's normal rewards rate with just a few extra clicks.

Gregory Karp writes for NerdWallet. Email: gkarp@nerdwallet.com. Twitter: @spendingsmart.

The article 6 Mistakes to Avoid When You Open a New Credit Card Account originally appeared on NerdWallet.

Get the latest local business news delivered FREE to your inbox weekly.

🎧 Is your savings account adding up in the way you'd like right now? A new study shows four of five Americans are considering other options.

🎧 While there might be little relief in sight, these changes can help you find savings with gas prices at record highs.

Some dividend-paying companies give you a unique opportunity to earn automatic pay raises while you sleep.

Amazon's stock split will take place on June 3, but don't expect to wake up to riches overnight.

Don't count on getting anywhere near this much money from Social Security when you retire.

This chart can help ease any worries about a stock market downturn.

The goal is quite attainable for many Americans.

Make the math behind building wealth work for you.

You're not necessarily doomed to a stingy benefit.

Portrait of a happy Latin American woman at home checking letters in the mail and smiling - domestic life concepts

Get up-to-the-minute news sent straight to your device.