<prompt> Human: Ive only had a credit card since February of this year and before that 1 student loan that is now closed, so Im a little green as far as the nuances of credit score go. I understand the factors of the score utilization, length of credit, payment history, types of credit, and credit seeking but Im not sure how to use these on a month-month basis. After pushing my utilization of the 2 cards I now have to 8590 this summer, I payed off 3000 over the course of September and October. My goal was to bring my balances to zero so that I could train myself to act the way I would once my 0 APR period is up in May. I reached my goal but my credit score took a HUGE hit of 65 points. I think the fact that one of my card limits went up by 40 is definitely a factor.As the title says I feel like there is no way I can keep my score from plummeting due to 0 utilization, and avoid the interest I WOULD incur were I not in this 0 APR period. Is there a sweet spot where the Interest is worth It in relation to say pointscash back? Should I look into getting a student loan instead of paying for school out of pocket, just to keep my score more stable? Any advice would be welcome and appreciated.  <response>: You should never pay a cent of credit card interest. Always pay your balance in full. You should never pay interest to build your credit score. Just use your credit card for normal expenses and pay it in full. 