You are here: Home › DIY › Jellyfish:plastic grocery bag/plastic water bottle/thread/food coloring. Flatten bag, cut off handle & bottom. Cut along both sides to split into 2 sheets, use only 1. From center sheet, fold tiny balloon for head, tie w/thread-not too tight. Leave little hole to pour water in head. Cut from edge to head for 8-10 tentacles. Cut ea again into 3-4 small strings. Trim into long & short pcs. Put water in head. Leave some air inside so floats. Fill bottle, add jellyfish & blue food coloring. Recap.