Because of this statement, I’m guessing that you understand some things beyond basic credit management (aka: pay off what you borrow). I’m going to go against the grain on this thread and say to disregard the folks preaching “pay off every balance” and the like. (No offense everyone)
Start researching how to leverage unsecured credit lines for cash to invest. In short, put all your USUAL expenditures on credit cards that you can (up to 30% total limit), pay them off by doing a balance transfer to a 0% card (pay the 2-4% transfer fee). Use the cash that you would have paid off your balances to dump money into a Roth IRA, 401K, etc. or into a brokerage account (watch out for taxes on this one!). Then just pay the minimum due on your credit card (typically 1-2% of your balance, at 0% APR).
As your credit history advances and the companies see you “carrying a balance” (remember, at 0% APR!). More companies will offer you higher limits. Rinse and repeat. I have many colleagues that do this and we all carry 0% APR balances of roughly $10-80K (depending on the investor’s aggressiveness) and just pay the 2-4% transfer fees each year. For each year that their accounts are yielding higher than 2-4% (which is most years), they are earning profit.
You could start now if you want. Based on your listed credit limits, you should have $2300 or so that you could play with, without negatively affecting your score. Remember, you are young and have time on your side. Stick to index ETFs and mutual funds, they are cheap and good for long term average growth (research SPY, XLY, VTSAX). S&P 500 has yielded on average 10.49% since the 1920s; if that continues, your $2300 would be about $124K when you are 60. The trick would be having a good balance transfer card acquired BEFORE initiating the overall plan and DO NOT fall into the trap of spending extra just because it appears that you have more cash on hand for a few months.
Good luck kid.