The easiest way to establish credit is to have someone add you to their account as an authorized user. You need to be careful when you do that, though. When you are added as an authorized user, the card issuer will report account activity on your credit report and the original card owner's. If you are irresponsible with the card, the family member or friend will suffer, and if either of you fails to make payments on time, it will reflect poorly on your credit report.