The secret to going from a credit score in the low 600s to excellent—without ever really checking it

Have you made a major jump in your credit score and would like to share your personal journey? Email reporter Elizabeth Gravier at elizabeth.gravier@nbcuni.com if you're interested in being featured in CNBC Select's new "Credit Scores: Then and Now" series.

Kara Stevens recalls her credit score at its lowest point being somewhere in the low 600's. When asked to pull her latest score for this story, her score by Equifax (one of the three main credit bureaus) calculated an "excellent" 766 using the VantageScore 3.0 model.

Below, Stevens, who is founder of the personal finance and lifestyle blog The Frugal Feminista, shares with CNBC Select her personal credit journey and the secret to her big credit jump.

Stevens graduated from college with a couple thousand dollars of debt on her first-ever credit card (a Discover card) and student loans. She wasn't paying back either, until she realized how quickly that mistake added up.

"I remember in college I would just buy things and assume they were automatically taken care of," Stevens says. "I'd open up the bills and see that the balance would keep going up even when I stopped buying things because I was getting all of these late fees." 

She credits her mother for helping her realize what was happening. "It never really dawned on me that I had to actually pay the money back, and that the bill was a financial consequence, a penalty, for not doing it," she says.

Stevens' credit score didn't change overnight — in fact, she estimates it took about seven years to become excellent — but she quickly read up on credit once she came to the realization of its importance.

Stevens remembers visiting the library and reading "Girl, Get Your Money Straight!" by Glinda Bridgforth as well as other books on credit responsibility.

"That book helped me really understand that there are books out there about personal finance specifically catered to women," Stevens says. 

She credits books to helping her understand the relationship between good money behavior and a successful future. Stevens says she also learned about the power of credit and credit scores, which was what motivated her to check her score for the first time ever and realize it was in the low 600's.

"That's when I first started to think about money management and the indicators that demonstrate financial health," Stevens says. This was her realization that a good credit score matters.

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An even better cash-back card for people with fair or average credit is the Capital One QuicksilverOne Cash Rewards Credit Card (see rates and fees), which offers a competitive 1.5% cash back on all purchases, with no limit on the amount of cash back you can earn. And cash back can be redeemed at any amount, without the typical $25 minimum some other cards set.

Though a lot of experts suggest you constantly stay on top of your credit score to know if it goes up or down, Stevens improved her score while barely checking it at all, except for certain milestones: a new job, getting married, signing for a new apartment.

But she did abide by one rule, and it's been her secret to raising her credit score from just OK to "excellent."

"I knew that if I paid my credit in full and on time, my credit score would go up, and that's always been my learning from the books," Stevens says. "I felt like checking it wasn't necessary if I knew I was doing the work of getting good credit."

Stevens notes that she stuck with her Discover card for a really long time and opened up a Visa card years later to get a better interest rate. She said she never closed her oldest Discover card based on strategies she read about the importance of showing a long credit history.

Her number one piece of advice to improve your credit score? No matter how often you check it, make sure your credit card payments are made on-time and in full.

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