All things low interest credit cards
If you go over, do everything you can to pay your balance down as soon as possible. Many credit card companies will let you go over your limit, but the interest rates they will charge you will be exorbitant, and the fact that you exceeded your balance may be reflected in your credit report. And, of course, always pay all of your bills on time. This includes your rent and utility bills as well as your student credit card bills. If you pay any bill, even the smallest, late, that fact can show up on your credit report as a black mark against you.