I know this is too late for your training session this time but... having run this one myself you can get a lot of mileage out of Golf. First give them the bit about not at the edge of a river/lake/stream, look up for "widowmakers", etc. Then, generally better than half of your adults will be golfers and most of the other half will be familiar with the game, particularly "reading the green".
Ask those that are Golfers to hold out their hiking poles and read the tent sight just like a green. Commission them to find the sweet spot (if one exists). Then once they do have them pass that "how-to" knowledge on to those that don't using the EDGE method. Then you can launch into the rest of the story.