What's Your Story Telling Process?

I've watched the movie twice now, and there are two a story telling beats that i admire very much. What may end up as just one throwaway line is, in fact, its own amazing story. I would love to hear about your process about figuring out what of those moments made it into the final version. There was something that was sort of irresistible in the story that was also true, which was that these people were a sort of professional spinners of fiction. That's what the 20 committee was.