18. The best way to improve your credit score is to pay bills on time and to borrow no more than 30% of your available credit.
It also helps to pay off debt rather than moving it around because the ratio of your credit card balance to your credit limit is key.

Say you owe a total of $2,000 on four credit cards, each of which has a $2,000 limit. Your total credit limit is $8,000, of which your total balance ($2,000) accounts for 25%.

If you transfer all your balances to two cards and cancel the other two, your total credit limit is reduced to $4,000, and your $2,000 balance now accounts for 50% of that limit.

Also, don't open new accounts when applying for a loan if possible.
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