Paying off your card right away is a bad way to build credit. It builds it slowly (if at all) because all it proves is that you can pay bills on time. Credit card companies and banks are only going to be interested in you if they can make a little money off of the interest on your balance. Any credit counselor will tell you that the best way to raise your credit score is charge a purchase (not a huge one) and then pay it off over a period of 6 months. For example, with my first credit card (also Visa) I bought a nice digital camera + accessories and pay it off over about a 6 month period. Continuing with this cycle will raise your credit score considerably and you'll receive higher limits, lower interest rates, etc.
Too many people are unable to handle credit responsibly and use it to their advantage and that's what leads to debt. Credit can be a valuable tool but only if you know what your'e doing and sadly most young people like me are pretty uneducated about it and not responsible enough to handle it properly.