Lies, lies, lies...How can I avoid them?

I have a big problem with lies. It’s like I can’t live without them. I tell lies every day without any serious reasons. Or sometimes to impress someone. It’s really hard avoiding it. Maybe I tell lies because I am afraid what is going to happen?? I really don’t know. But I noticed that people don’t trust me no more. I try to tell the truth but always something happens and everything goes wrong with result, a lie.
One lie brings another. And my whole life is going to be just fake. Sometimes I believe my own lies!!
How can I stop telling lies?