My credit score is 830 and I have never asked or bothered about how to improve my credit score. I have gone several years without knowing my credit score, but these days, every bank account or credit card account shoves it in your face, so that's how I know.

To me, it's just common sense. Pay your bills on time. I've always paid my credit card balance in full because I would hate to pay high interest on cc bills. I've always had two credit cards. One to use and one for backup. In the first few years of using credit cards, my credit utilization may have been 50% or more, but I wasn't buying new cars then. You may want to reconsider and get a used car instead?