Since we're all young, may I recommend the slow and steady way, as well as general financial advice...
CDs are good, as mentioned. If you have capital now is a good time to invest in stocks, especially mutual funds, but that requires a decent initial investment that many of us young people don't have.
Look into roth IRA! It's untaxable once you're set in and no penalties for withdrawls unless you try to pull out gains. Combine this with the next step.
Put aside a dedicated amount for savings out of every paycheck. 10% may seem steep or 'not much to spend' as you spend your entire paycheck, but 'old people' I know who have done this and invested in an IRA since 20 years old have saved over a million $ by retirement at 60.
GET A CREDIT CARD. But don't be an idiot with it. Use it to buy things you need like food and gas and always pay it off every week. This is very easy nowadays with online banking, if you have access to wells fargo or citibank especially. This will build CREDIT over a few years if you pay back on time, and as long as you pay every week you don't accumulate interest like other idiots. Building credit gives you access to better loans for everything, financing on cars, phone plans, apartments, houses, and is crucial if you're a newly independent adult (or hoping to achieve independence soon) in America.
And finally the most important financial advice you'll ever receive...
Before you spend money, consider if you really NEED it or if you merely WANT it. If you don't need it, think about why it's worth the money and your time. Spend accordingly.