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DIY Under the Sea Costume: 40-Min Cardboard Build

DIY under the sea costume built from clear umbrella, pastel ribbons, and red shirt and pants, plus red mittens
AI-generated concept photo

Pictured: the jellyfish, clownfish, and crab.

Time40 minEffortEasy

⏱️ We timed it, but results may vary.

Plan this costume →No signup · 2 minutes.

A jellyfish from an umbrella with ribbon tentacles, a crab from red clothes and claw mittens, plus fish, seaweed, and waves. The umbrella is the genius move. Forty minutes, easy: a clear umbrella, pastel ribbons, and a red shirt and pants. The tentacles should hang to knee level; short tentacles read as skirt.

2 of 7 things covered, counting basics we assume you have.

Tap a supply to tick what you own.

Still need:

Jellyfish: 1 clear umbrellaString / yarn / ribbonCrab: red shirt and pantsSeaweed: green clothesWaves: blue sheet
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Tip: tape small silver star stickers to the ribbons as bubbles.

Steps

  1. Give each person one sea creature.
  2. Buy the clear umbrella, pastel ribbons, and green streamers.
  3. Pull the colored clothes from closets.
  4. Safety: Cut the ribbons slowly and keep fingers clear of the scissors. Hold the clear umbrella high and keep the tentacle ribbons clear of faces.
  5. Cut one ribbon first.
  6. Tape it to the umbrella edge to test the drape.
  7. Jellyfish: cut the pastel ribbons into 3-foot lengths.
  8. Tape them to the edge of the clear umbrella like tentacles.
  9. Hold the clear umbrella overhead.
  10. Crab: dress in red.
  11. Slide the red mittens or red socks onto the hands.
  12. Hold both hands up, fingers pinched like claws.
  13. Fish: tape the cardboard fish cutout to the chest over the silver clothes.
  14. Seaweed: tape the green streamers to the shoulders and arms.
  15. Everyone holds the blue sheet behind the group as a wave backdrop.
  16. Optional pro finish: tape small silver star stickers to the ribbons as bubbles.

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Common questions

Is the umbrella safe in a crowd?

Hold the clear umbrella high and keep the tentacle ribbons clear of faces. In tight crowds, carry it closed until there is room to open it.

What if it actually rains?

The jellyfish wins: the umbrella is real and functional. The ribbons may get soggy, so use crepe paper only if the forecast is dry.

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