These following questions - taken from the OUP new matrix series - offer students great scaffolding to tell/invent a story that happened to them. I gave an example first revealing one sentence at a time and then let them loose.
Where were you?
Who were you with?
What the weather and the place was like?
What you were doing?
What preparation you had made before?
What went wrong?
How you solved the problem?
How you felt at the end of the experience?