Most people know that paying bills on time is a must to keep credit scores high. But credit scoring models are complex, and there are many other factors involved in winning the credit score game, say experts.

The success of FICO scores has spawned numerous other credit scoring models, all of which have slight variations in how they profile consumers. Here's how to make sense of the different credit scores that are available to you.

Financial experts recommend that you check your credit report at least once a year — not only to look for signs of identity theft, but also to avoid errors that could pull down your credit score.

Of all the different components of FICO scores, a consumer's credit utilization ratio is perhaps the most elusive and least understood. But it's important that you understand your credit utilization ratio in full so that you can maximize your credit score.

People with no credit history or bad credit are often caught in a Catch-22 — they need to demonstrate good credit behaviors to develop a credit history or improve credit, but they can't get any credit to do so, because they have bad credit or no credit record.