Balloon backdrop!! No tutorial, but I would try to duplicate this by having a 2x4 as long as the desired backdrop width and place it on the floor. I would tie each string to the 2x4: the shortest strings on the darkest balloons and make the strings vary in height, with the lightest colored being the longest strings.
Some of the jell-o cups we placed candy sharks and swedish fish in once the jell-o had begun to set. For the others, I spread a little Cool Whip on half the ocean, then topped with crushed Graham Crackers to create waves and sand. We topped a few with fun cocktail umbrella’s and placed little glass marker mermaid’s in the water swimming to the surface.