Using credit cards to improve your credit score is something I highly recommend. The credit score game is really stupid, but it's valuable to have a good credit score. If you ever want to own a house, you get a much better deal on mortgages if you have high credit, and likewise for auto loans or any other sort of loan. You never know what might come up in life where you might need to borrow money to save your ass, even disregarding home ownership. It's very easy to open several credit cards, and buy one thing on each of them each month (like buying gas, or groceries, something you'd already be buying I mean), and then pay them off immediately. Doing this will build your credit. I recently found out that you get a penalty to your credit score if you have less than 10 accounts on your record, whether they're open or closed. Thing is, after a certain number of years, inactive stuff drops off your report. I found this out because I have been working my credit back up since I declared bankruptcy at the end of a parasitic relationship/opiate addiction combo that sent me hugely into debt that was insurmountable for me. I've been doing great, but my score suddenly dropped by like 40 points, putting me down into a lower category. It was because like 5 old credit accounts that got closed/paid off by bankruptcy dropped off my credit report all in one month. You'd think having the evidence of discharged debt removed from your report would make your score go up, but no, apparently they care more about how it now appears that I "only" have 4 loans/accounts on my report.
However my bankruptcy is going to drop off my report in like a month and a half so I expect it will jump back up then, which is good because I'm trying to refinance my mortgage.