I wanted a bioluminescent jellyfish hat for ballroom dancing, so I safety pinned a modern woven trilby? to a beat-up but solid 1950s picture hat with headband to ensure a snug fit. From there, I constructed a solid metal frame (20″ hanging basket painted ocean blue with silver glitter and large light cover) to attach all ruffled tentacles, EL wires, LED fairy lights, LED cabinet round push lights; reused off white tulle to hide battery packs and light switches under the hat; sewed iridescent fabric and 1/4″ elastic cord into a giant rounded shower cap that can be easily removed to turn on/off lights; and gathered the iridescent ribbon in the middle to simulate tentacles. To stabilize this heavy beast, I added tulle straps to the edges of the metal frame to tie a bow under my chin and then stitched 2 elastic cords together to attach to the inside hat for a tight fit under my chin. The hat is not ideal for ballroom (no underarm turns!) but was fun to build and wear – especially dancing with a pirate under black light – it looked like we were dancing underwater!

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