I think that for my daughter, her "storytelling" and lying are easily discernible. She does not lie very often. I think I may have caught her in 2.
Finding out why, and make sure you sit down and speak face-to-face, eye-to-eye. When my 8-year-old daughter recently told a lie, it was because I was on the computer upstairs and she was downstairs, and she was dishonest about what she ate for breakfast. In this case it was a doughnut, and she said it was bread. When I discovered the half-eaten doughnut, I asked her "eye-to-eye" what she actually ate for breakfast, and she told the truth.
I told her that I prefer her to be honest about her breakfast choice, even if it isn't the best choice - that truth is better. We also discussed the issue of the habit of lying taking away your freedom...and adding to the fear of being caught. The truth really does set one free.
Since my husband is the one who brought home the doughnut, and therefore presented the temptation....he was instrumental in the issue. He said that he wasn't going to bring home any doughnuts for a while because she had disappointed him by lying around it, and not honoring his intention for the doughnut - a dessert to be shared by the 3 of us.
Also, afterward, it may also be effective to discuss a story about a child who lies and what happens to her or him...such as "Peter and the Wolf" (I think it's an Aesop fable)..
It is important that the "discipline" fits the "crime," and that the only way to make amends for a lie is an apology and resolution to tell the truth from then on in. Next time I ask her something, it will be face-to-face. It was too easy for her to lie when she isn't looking at me face-to-face.. It decreases the temptation if that temptation is there.