With the right travel credit card, you can rack up airline miles, hotel points, and flexible travel credit you can use to see the world. However, you'll earn a lot more points if you spend strategically. These 25 tips can help you maximize the rewards you earn on everything you buy.

Many rewards credit cards have bonus categories that dole out considerably more points, which is why you should choose a travel card that makes sense with your spending. If you spend a lot on airfare, for example, it would be smart to pick up a card that offers more points on air travel like the Platinum Card from American Express.

Airlines like Southwest and American offer shopping portals that let you earn miles for each dollar you spend at participating stores. By utilizing a portal anytime you shop online, you can rack up a lot more airline miles over time.

Chase Ultimate Rewards also offers its own shopping portal. This portal makes it easy to earn extra points when you shop online at stores like Home Depot, Dick's Sporting Goods, and Sephora. Fortunately, all you are required to do to earn those extra points is click through the portal before you shop.

Rewards cards that offer 5% categories can be especially lucrative. The Chase Freedom and Discover it are two cards that fall into this category, offering 5% back on your first $1,500 spent in rotating categories like department stores, wholesale clubs, and Amazon.com

If you want to make sure you're paying many of your bills with a rewards credit card, it can help to set them up on autopay. Doing so will ensure each bill is automatically paid with the rewards card, ensuring you don't forget to pay with credit.

A lot of people don't realize they may be able to pay for health insurance or auto insurance with a travel credit card without paying a fee. If you want to earn more travel rewards over time, it can definitely pay to check.

While this tip might seem like common sense, it's extremely important. Make sure you're using your rewards card for all your regular spending including purchases like gas and groceries. Even rewards earned on small purchases can add up in a big way over time.

If you dine out a lot, you should explore rewards cards that offer more points on restaurant purchases. The new American Express Gold Card is a solid option because it offers an annual dining credit at participating restaurants as well as 4x Membership Rewards points at U.S. restaurants.

Some airlines offer dining clubs that let you earn more miles when you dine at participating restaurants. The Southwest Rapid Rewards Dining Club is a good example, and you can even earn a signup bonus for dining at participating restaurants within the first few months of membership.

While having one spouse rack up travel rewards can be a lucrative endeavor, two is even better. Make sure your spouse is using travel credit cards for all their spending, and note that you can both get the exact same travel cards - even if you live at the same address.

You can also add authorized users to all your favorite travel credit cards. If you have a teenager who does some spending on their own and you trust them, this can be a great way to earn more points and miles over time.

If a family member is making an expensive purchase and they plan to pay in cash, offer to pay with your credit card. You can earn more rewards this way and your family member can give you the cash instead. Everyone wins.

Also remember that you don't have to stick to a single rewards credit card. You can sign up for two cards, three cards, or a multitude of travel credit cards if you're able to keep track. Doing so can help you earn more signup bonuses as well as better optimized rewards on your regular spending.

Speaking of signup bonuses, they offer the great potential to maximize rewards on your everyday spending. Many travel credit cards offer 50,000 points or more if you're able to spend $3,000 or $4,000 on your card within a few months of account opening.

You can also pay taxes with a credit card, although there may be fees involved. If the fees you pay are less than the rewards you earn, however, this can be a good deal. Make sure to compare fees and potential rewards before you decide.

Plastiq.com is a service that lets you pay any bill with a credit card -even bills that are hard to pay with credit such as rent or your mortgage. This service does charge a 2.5% fee, however, so you have to make sure the rewards are worth it before you move forward.

You can occasionally earn more points and miles by booking certain types of travel through partners. By booking hotels on the Southwest Airlines website, for example, you can earn up to 10,000 Southwest Rapid Rewards points per night.

Choosing cards that let you combine points can also help you strategize your rewards even further. A good example is signing up for the Chase Freedom for the 5x categories and the Chase Sapphire Preferred for 2x points on dining and travel.

Points Hound is a website that lets you earn airline miles for each hotel stay you book. Currently, you can earn up to 10,000 miles for a single night stay at over 300,000 hotels worldwide with programs like American AAdvantage, Frontier Airlines, and United MileagePlus.

Loyalty programs like Hilton Honors and Chase Ultimate Rewards make it possible to refer people to their credit cards and earn more points in the process. If you love your travel credit card, why not get your friends in the game as well?

Kiva.org is a website that lets you loan money to people around the globe. Not only do they report a 96.9% repayment rate, but you can fund your loan with a credit card and earn rewards in the process. Since many Kiva loans are granted to in-need citizens in impoverished countries, you are also helping someone in the process.

Banks like Citi and Chase are known for offering points for consumers who open a new checking or savings account. Right now, Chase is offering a new Chase Sapphire checking product that comes with a 60,000 point signup bonus. You do have to hold the Chase Sapphire Preferred or Chase Sapphire Reserve to qualify.

Some people with experience in a certain type of product get in the buying and reselling game to rack up more rewards. If you can buy a product at a discount with a travel rewards credit card and sell it at a profit, you can earn all kinds of rewards over time.

Some travel enthusiasts also buy gift cards to earn more rewards over time. They usually do this by purchasing gift cards through a portal that offers cash-back, or at a grocery store with a card that offers extra points on grocery purchases.

Some airlines like American, Southwest, and Delta offer special deals on vacation packages that include hotels and airfare. Make sure to utilize these deals when you can because they often offer bonus points when you book. With Southwest Vacations, for example, you can often earn up to 10,000 points for each vacation package you take advantage of.