A lot depends on the job you are applying for, and what you are trying to "prove." I look at this as a question of planning and organizational skills, your ability to delegate, and use of available resources.
I was told to create and carry out a "table-top" aircraft disaster exercise. (A walk through, without actual aircraft or casualties, just done on paper). I had never even participated in one! I found a free on-line course through FEMA, and quickly worked through it. I then talked to other people in the department who had designed previous exercises. I talked with Mgt to find out if there was anything particular they wanted included in the exercise (sometimes an exercise will have the police chief "incapacitated" to see how the dept. functions without him/her in such a situation).
The next step was planning: in addition to creating the storyline for the disaster (which, I am not a creative writer!!), there were so many other things to do!
- identify who to invite, and invite them
- find a place for parking for the participants
- get signs made so they would find their way to the exercise rooms
- reserve the rooms we would be using
- coordinate with maintenance to get the carpets and furniture cleaned and set up
- Get the Air Conditioner people to make necessary manual adjustments to accommodate the large number of people (old units, needed rooftop adjustments)
- Figure out the needed supplies and place orders (white boards, markers, erasers, flip charts, etc)
- Order lunch for the attendees
etc etc etc. I started calling myself "the wedding planner!" To track all this information, I created a spreadsheet. One page for things I had to do, with my point-of-contact's email and phone #, and comments as to what needed to be done, and deadlines. Another page for all the contact information of those who would be attending. This kept me on task, and kept me from forgetting to do something that needed to be done!
The exercise went well, and we received many compliments!
When telling a story in an interview, you want to use the STAR format
S: what was the SITUATION you were faced with?
T: What TASK did you need to accomplish?
A: What ACTION did you take?
R: what was the RESULT?
Your example may be less intense, depending on your life experience. But try to find something that highlights the skills that are important for the position. You could be team captain of a losing sports team that has lost all morale and has stopped trying to win; a store employee whose manager was suddenly taken away by ambulance and you are now left in charge for the first time in your life, etc.
Let me know if I can be of further assistance!