Jellyfish Halloween Costume Diy . You can easily order it online. Glowing jellyfish costume instructions we took an old sombrero and spray painted it blue. Jellyfish costume Jellyfish costume, Creative halloween costumes diy from www.pinterest.de Giving it a shiny wrap. Umbrella, tulle, lights and bubble wrap. To finish it all,i made a huge 6 gore tulle poncho.