The key for us credit noobs is to NOT go charging up extra stuff and then having to struggle to pay it off.
Instead, when you have the cash in hand and are ready to pay a bill or go to the grocery store, instead of paying out of your bank account or writing a check, pay on the credit card.
Then, immediately pay off the credit card with the cash you already have in your bank account. NEVER EVER EVER use the card unless you already have the cash to back it up. I happen to use Bank of America for my checking acct as well as the credit card, so I can easily go online and force myself to transfer money to the card to pay it off.
The more positive activity you can generate on your card, the more your score will rise. It will also show future creditors that you promptly pay off your debts instead of stringing them along barely paying the interest.
Great site to learn all the little tricks and really a better place to ask your question (after using the search function and reading the faqs):
www.creditboards.com