One of the little cruelties of life is that when you need credit the most, lenders are the least likely to give it to you. When it's hard for you to pay your bills, like when you're behind on your car payments, have maxed out all your credit cards, and can barely pay your rent or mortgage, your credit score goes down. Even if you make all of your payments on time, credit reporting companies can tell lenders that you are at your limit, that you have maxed out all of your existing lines of credit, and that you have been looking hard for more. Lenders will think very badly of you if you do this, and they will be much less likely to give you money.
Between Jobs
When you are between jobs is one of the times you are most likely to be in this kind of situation. There are a million reasons why you could lose your job, and many of them won't be your fault. If you're in a lot of debt and this happens to you, things can quickly get out of hand.
Even though it may seem obvious, the best way to get out of this situation is to find a new job as soon as possible. Most of the time, you can go back to work in a month or two, so if you have enough money to get by until then, you'll be fine. But it's not always easy to find a new job quickly, especially if you lost your old job because of problems in your industry or area.
Insurance
Credit protection insurance is something else you might want to think about. You will need to have bought this insurance policy before you lost your job. If you did, there's a good chance that you'll be covered for just this kind of thing. Most credit protection plans say that if you lose your job through no fault of your own, they will pay your bills until you find another job. They have a lot of strict rules, like expecting you to take the first job offer you get, even if it doesn't pay as well as your last job, etc.
Alternatives
You could also borrow money to get you through until you find a new job. Even though it may seem unlikely that a lender will give you money if you don't have a job, there are times when they will. If you have a good history of paying back loans and a good chance of getting a job soon, they may be willing to help you. This is especially true if you can offer them security, like your home. If you do go this route, though, make sure you are sure you will find work before you put your home at risk.