There are many factors that go into calculating your credit score, including your payment history, the length of your credit history, and the types of credit you use. As a result, your score accounts for both positive and negative credit information. While late payments will lower your credit score, establishing a good track record of payments will improve your score.
The first step in improving your credit score is requesting your credit report. In this video, a financial advisor explains how to request your report from the major three credit bureaus. He also explains how to clear up any errors on your report by sending a letter.