A simple way to help people tell a story by providing prompts that keep the story moving and demand richer description and reflection.
Sitting in a circle, participants take turns telling a story with the facilitator (or as Boal says, the Joker) providing the links:
Participant 1: "My friend called me this morning and told me she was going to quit school..."
Joker: "because..."
Participant 2: "...she needs to make money and she feels like school has no meaning."
Joker: "But..."
...
The idea is not to steer the story to a particular conclusion, but to prompt people to flesh the story out, to make the characters multi-faceted, and the story complex. In the example above, the joker says "But..." to generate some tension. The next participant, is free to take that "but..." anywhere s/he likes:
"but I told her I think she is just depressed"
"but she has plenty of money"
"but everyone feels that way"
The joker's job is to keep the story moving and incite creativity. Of course, because people rely on what they know, feel and imagine, the story that emerges may very well contain interesting contradictions or gaps that can be discussed afterwards...
The joker role can be rotated each time, one turn behind the speaker.
At the end (or in the beginning), it may be useful to have participants note the words the joker used and extend the list: but, then, so, and, meanwhile, of course, suddenly...