1. Print out guidelines to use at the event. 2. Make sure you have a timer/stop watch with you. (and a coin) 3. Two days before the event you will receive a copy of the cases and the question to ask the students for each case. 4. You might like to make up a sign to hold up when the student have "30 seconds left."
You can see the format of a face to face event here; (You will need to make the adjustment for an online event.)