Lying is a full time occupation, even if you tell just one, because once you tell it, you're stuck with it. If you want to do it right, you have to visualize it, conjure the graphics, tone, and sequence of action, then relate it purposefully in the midst of seemingly spontaneous dialogue. The more actual the lie becomes to the listener, the more actual it becomes to the teller, which is scariest of all. Some people really get to believing their own lies.