improve my credit score to 700

Just paid off 2 credit cards tonight and 2 student loads completely paid off. Oh yeah! Feels good! Only 1 debt more to pay off. I feel disciplined and my overtime and hard work is not going to waste. I’m trying as much as possible to be debt free before I get married. And at this rate, I might be able to do it after all.

How are you people building your credit scores. The only ways I know is to keep the balances on your credit cards as low as possible, be on time with all your payments. I’m paying off my car. Would you recommend any of those agencies that help lower your score, and why?