Start with Your Credit Score
Your credit score is the first filter, because it sets the cards you can actually qualify for. The best rewards and benefits (premium travel cards, high-rate cash back) generally need good to excellent credit (670 to 850 FICO). Fair credit (580 to 669) is a thinner field. Below 580, you are mostly looking at secured cards built for rebuilding credit.
Check your score before you apply. It is free. Most banks, credit unions, and services like Credit Karma and Experian give you the number. Knowing it keeps you from burning a hard inquiry on a card you will not get, and sets realistic expectations for what is on offer.
If you are close to a tier line, say, 665 when 670 is the typical cutoff for better cards, two or three months of paying balances down and not opening anything new can push you over the line and unlock better options.
Pick Your Primary Goal
One question narrows the field: what do you actually want this card to do?
To earn rewards: pick between cash back (simpler, useful everywhere, worth exactly what the card says) and travel points (higher potential value for frequent travelers, more to manage). If you travel internationally more than twice a year, a travel card with no foreign transaction fee earns its keep.
To pay down debt: a 0% balance transfer card with a long intro period (15 to 21 months) stops interest cold and lets you knock out principal faster. The 3% to 5% transfer fee is almost always less than the interest you would have paid.
To build or rebuild credit: a secured card from Discover, Capital One, or a credit union builds payment history with a refundable deposit acting as collateral. Most graduate to unsecured cards after 7 to 12 months of responsible use.
To finance a purchase: a 0% purchase APR card lets you spread a big purchase interest-free over 12 to 18 months.
Match the Card to Your Spending
Pull three months of bank and credit card statements. Find where the money goes. If restaurants and grocery stores eat 40% of your spending, a card that earns 3x to 4x in those categories will beat a flat-rate card over a year. If your spending is spread thin across categories, a flat-rate 2% cash back card is simpler and usually wins.
Annual fees need a break-even test. A $95 annual fee card has to return at least $95 more in value than a comparable no-fee card to earn its place. Run the numbers with your actual spending and compare the rewards to the fee. If it does not clear, skip it.
Look at the Full Package
Beyond the earn rate: the sign-up bonus (often $150 to $500, and usually the most valuable thing in year one), the APR (critical if you ever carry a balance), foreign transaction fees (3% is standard, many travel cards waive them), purchase protections (extended warranty, cell phone protection, purchase damage), and travel protections (trip cancellation, primary rental car coverage).
For most people, the sign-up bonus is one to two years of rewards earned up front. If the minimum spend to grab the bonus lines up with what you would have spent anyway, it is easy money and makes year one a lot stronger.
Pitfalls to Skip
The biggest mistake with rewards cards is carrying a balance. Credit card APRs typically run 20% to 28%. Any interest you pay on a carried balance wipes out the rewards and then some. Rewards cards only pay off for people who pay in full every month. Carrying a balance to chase rewards is dumb math.
The second mistake is applying for too many cards in a short window. Each application is a hard inquiry. Multiple inquiries in six months can drop your score noticeably. Be picky. Apply only for cards you will actually use and that fit your profile.