Find a friend's pool in either late Spring or early Fall (need a cool night, but still want swimming to be an option). Unbeknownst to the friend, turn off the heater mid afternoon, allowing the water to cool during the evening. Overnight, fill the pool with Jell-O packets. An average-sized swimming pool (15' x 30') holds approximately 20,250 gallons of water or 324,000 cups. Therefore, you will need 92,571 packets of Jell-O or 259,200 if you want to make it one gigantic Jell-O Jiggler. You can also get someone to fall asleep in the bathtub and pour Jell-O in while they sleep and hope it congeals.