The best way to handle this is first pull your credit reports from the three major credit agencies – Experian, Equifax and TransUnion. And this can be done free of charge once every 12-months through the site AnnualCreditReport.com. Go through each of the reports as thoroughly as possible looking for any inaccuracies, like – incorrect information on collections, judgments, balances, new accounts, and payment history.
If you have missed payments, get current and stay current: the longer you pay your bills on time after being late, the more your FICO Scores should increase. Older credit problems count for less, so poor credit performance won't haunt you forever. The impact of past credit problems on your FICO Scores fades as time passes and as recent good payment patterns show up on your credit report. And good FICO Scores weigh any credit problems against the positive information that says you're managing your credit well.
This is easier said than done, but reducing the amount that you owe is going to be a far more satisfying achievement than improving your credit score. The first thing you need to do is stop using your credit cards. Use your credit report to make a list of all of your accounts and then go online or check recent statements to determine how much you owe on each account and what interest rate they are charging you. Come up with a payment plan that puts most of your available budget for debt payments towards the highest interest cards first, while maintaining minimum payments on your other accounts.