All good advice so far.
I will add that you should consider was your future plans are? Do you expect to need good credit in the future? Will you finance large appliances, vehicles, a business? If a house is your only potential future debt, you could probably just focus on keeping your cards paid off and forget credit scores entirely.
I used to play the credit score game: constantly monitoring my debt/credit ratio, increasing my limit, trying to guess if it was the right time to open a new account, etc. I stopped when I heard that SoFi* was doing away with using a FICO score as a baseline for mortgage approval. They still care about your credit HISTORY, but mostly they're trying to look at if you're a safe bet (good income, reasonable house price, responsible on time payments, etcetera). Except for my future mortgage, my credit score is effectively meaningless.
I'll continue to pay my bills on time, in full, while leaving plenty of credit for a real emergency, but I'm done with the micromanaging just for the score.
*Not a shill