Carefully review older debt that shows as charged-off. Before contacting the creditor or collection agency, check your state laws to see if the debt is statute-barred or time-barred, meaning that it is too old for creditors to attempt further collection. If it is not statute-barred, even contacting the creditor can re-instate the debt as currently collectible, which can drop your score.
A good idea would be to keep three to four credit card accounts open, but only use one or two of them; put away or cut up the others. Once you have paid off a card, though, keep the account open, even if you don’t want to use it anymore. Closing a card will lower your credit score, even if you always paid on time and never carried an outstanding balance. If a card's high annual fees are making it undesirable, try asking the credit card company for a downgrade to one of their free or lower-fee cards. This allows you to maintain a longer history with the company, which is important for a healthy credit score. The company will report to the credit bureau that you have a good record with them, which will increase your credit rating.
Next, estimate your monthly spending habits for other expenses such as gas, groceries and entertainment. Create a limit, based on your income, of what you can spend in each of the different categories of expenses. For example, if you tend to spend $400 a month on groceries, try to stick to $300 a month on groceries by making changes like buying generic brands, using coupons, and resisting impulse purchases.