All you really need to start building credit is your social security number and something that reports to the credit bureaus. Assuming you have the first, credit cards are often the easiest way to gain credit and start building your credit history. If you are in school,
student credit cards are often the best way build your credit file since they have lower requirements. They tend to have much lower limits but it is a great starting point. If you go this route, you will want to find a credit card with no annual fees since the goal is keeping this credit card for a long time to build your credit history.
If you are finding that you can’t get approved for a credit card, you can look into secured credit cards. These credit cards have guaranteed approval but they also have hefty fees.
Secured credit cards will provide you a credit limit equal to your deposit. Once your score moves past 650, you should look for a lower cost unsecured credit card.