Although the media would have you believe life ends after your 20s, the reality is that it often gets better. You're smarter, wiser, and better able to tackle the problems life sends your way. What's more, you're also part of the primary marketing demographic; people in their 30s make up the largest portion of the U.S. population, with 14% of residents in the 30-39 age bracket.

One of the best things you can do with that age-born wisdom is take better care of your finances. And this extends to your credit cards. Here are a few smart credit card moves you can make in your 30s to improve your financial health -- and life in general.

1. Pay off your credit card debt

This one is a good move no matter your age, but it can be especially important in your 30s. That's because card debt can be a big red flag when applying for other types of credit, such as auto or mortgage loans.

There are a variety of methods you can use to tackle credit card debt. If you have multiple credit cards with balances, consider using one of these two popular approaches:

• The Avalanche Method: With this strategy, you organize your debts according to the interest rates. You pay off the card with the highest APR first, then focus on the next-highest rate, and so on. With this method, you save the most money, since your most expensive debts are paid off first.
• The Snowball Method: With this strategy, you organize your debts according to the size of the balance. You pay off the smallest balance first to get an early win. Then, move on to the second-smallest balance, and so on. With this method, you get consistent motivation from seeing your debts disappear. You can use our debt snowball calculator to explore this method.

2. Upgrade your low-value cards

Most of us spend our 20s figuring stuff out. This time can include college, entry-level jobs, and starter credit cards. By the time you're in your 30s, however, you may be in a much better place in terms of your credit and finances.

That makes now a good time to explore your options for upgrading old credit cards. For example, maybe you still have a student credit card from your first years of college. That card probably isn't nearly as useful now as it was then, so it may be time to trade it in for something better.

In some cases, you may be able to request a product change from your issuer. This allows you to keep the credit line intact while providing a card that better suits your current needs. The downside to this method is you probably won't be eligible for any sign-up bonuses.

Alternatively, you can always cancel the card and reapply for a new card with better perks and rewards. Closing card accounts can have credit repercussions, but as long as the rest of your credit profile is strong, they should be minor.

3. Optimize your purchase rewards

While you're thinking about new cards, make sure you're taking into account your current spending habits. The things we spend our money on in our 30s are usually vastly different from what we purchased frequently in our 20s. (I spend way less on bar tabs now, and way more on home utilities).

Aim to maximize your credit card rewards by choosing cards that offer high rewards rates on the categories in which you spend the most. Are your grocery store bills a big chunk of your monthly budget? A card with 6% cash back on grocery purchases could earn you a lot of rewards.

4. Take advantage of travel perks

Whether you're taking your growing family on summer vacation, or exploring international destinations with your partner, the best travel rewards cards can take your experience to the next level.

Several travel cards offer complimentary airport lounge access, for instance. This can turn a long layover into an enjoyable interlude. And hotel elite status, another common card perk, can save you money with free breakfast or room upgrades.

Most travel rewards cards require at least good credit. And the top cards will come with high annual fees, so do the math to make sure they're worth the cost.

With age comes wisdom -- and better credit cards

It's perfectly natural to mourn your 20s. (I personally miss standing up without clicks and pops!) But your 30s can also be pretty awesome. You're more established, have more confidence, and can use your life experience to avoid some of the silly mistakes you made when you were younger.

So, while it can be tempting to hang on to certain aspects of our youth -- your old credit cards may not be worth the sentiment. Your 30s are a perfect time to tackle old debts, upgrade old cards, and take advantage of new access to better cards and rewards.