FICO credit scores can go up to 850, but seeing that number is rare. What does this mean? You should aim to grow your credit score even higher. We know you can do it.

When it comes to credit scores, there’s almost always room for improvement. If you’ve pulled your score and you’re not satisfied with the number you received, there are several strategies to boost it. But first, you need a little insight into how that score is calculated.

Fair Isaac, the company that generates your FICO score, uses five major categories of information, all of which was reported to the credit bureaus by your lenders. Each category is weighed differently. Here’s a break down:

35% is based on your payment history, and whether you pay on time.
30% is the amount you owe. Credit card debt is going to drag your score down more than installment debt like mortgages, auto and student loans will.
15% is made up of the length of your credit history, with longer relationships with creditors always viewed as better.
10% is how often you shop for credit and open new accounts.
The remaining 10% is based on the kind of credit you have. A mix of cards and loans is best.

If you want to raise your score, you can do a few key things.

Pull your credit reports. The three major credit scoring bureaus, TransUnion, Equifax and Experian, will each allow you one free copy of your report a year. You can get yours (and I suggest spreading them out by pulling one every four months) on annualcreditreport.com. If you find an error on your report, you should dispute it. Simple mistakes – the wrong address or a misspelling of your name – can be fixed by calling the creditor and asking for an update. If they won’t oblige, or the error is more complicated, you should dispute directly with the credit bureaus. You can do this online.

Pay your bills on time. One day late is still considered late, and just one late payment can lower your score.
Don’t carry debt. You want to aim to use less than 10% of the total credit available to you.
Hang onto old cards. Your credit score benefits from long relationships with lenders, so cut them up, but don’t cancel them if you can help it.
Stop shopping for new credit. Every time you apply for a new card or loan, the lender takes a peak at your credit history, which dings your score.

Spread your debts around. The mix of credit you have in your file—mortgages, student loans, auto loans, credit cards—shows that you can juggle debt from multiple sources.

Remember that time – and patience – are key. You shouldn’t expect a change overnight, but you will see improvement over the course of 12 to 18 months – shorter, if your score is already fairly high and you’re just looking for a bit of jump (FICO scores range from 300 to 850; the higher, the better).

By Jean Chatzky, SavvyMoney.com