Every time you retell the story it gets a little better. Notice when it stops being true.

Stories improve by themselves. A detail that got a laugh gets sharper, an inconvenient bit drops out, and none of it feels like lying because each edit is tiny and the shape is still right. Twenty tellings later the version in your mouth and the thing that happened have separated, and you may not be able to find the seam.

Pick a story you tell a lot and try to remember the first time you told it. Notice which parts have grown and put a couple of them back the way they were. The plainer version is usually still good, and it has the advantage of being what happened.