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Adorable DIY Jellyfish Costume

Today’s contributor is Jill from Snugglebug University.  All posts written by Jill for Make It and Love It can be found HERE.

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Hi, it’s Jill from Snugglebug University.  Today I’m going to share my daughter’s Halloween costume with you!

This year marks a big change for us in the costume department, and it’s a bit bittersweet!  Usually Lu’s costume requests involve princesses, fairies, or a Disney character of some sort so it surprised me  when she requested a jellyfish costume!  Sigh, she’s growing up!

It’s no secret that this girl loves the ocean though–she did beg me to make a whole bunch of jellyfish to hang from the ceiling of her room!   I love that the costume feels a bit magical though.  All in all, good choice Lu!

I usually imagine jellyfish as being white or a light pink, but Lu was set on being a lavender jellyfish.  It suits my purple-loving girl so well!

The dress is made with several ruffles, but it’s actually quite a quick sew.   You’ll notice that the form of the dress is really simple, and that makes it easy!  There are no zippers or buttons! It goes on straight over the head.

The main part of the dress is made of a velour fabric which is really nice because it won’t fray.  This means there really isn’t a need to finish the edges.

We already had a bubble umbrella at home, which made this costume even quicker to throw together.  I threw over some sheer fabric, tied a boa to each of the edges and added some ribbon “tentacles”.  If you want to make this costume even simpler, you could just get a solid colored shirt and leggings and just let the umbrella be the main attraction!

Boy does our umbrella shine though!  The umbrella has lots of feathers and glittery feathers.  I also found some simple LED lights to wrap around the inside of the umbrella.  They are going to look so cool when we go trick or treating at night!  The umbrella really could be a costume all in itself!

Alright, who is ready to make a jellyfish costume?

Here’s what you’ll need:

  • 1 1/3 yard of knit velour  (It’s stretchy!)
  • 1 yard sheer fabric
  • 1.5 yard coordinating sheer for the ruffles
  • 1.5 yard sheer fabric to cover the umbrella (I used the same fabric type as the ruffles)
  • LED lights  (I bought mine on amazon)
  • 2 boas (I used two from the dollar store)
  • 6-7 yards ribbon to attach to the ends of the umbrella
  • a bubble umbrella


OK, are you ready to start sewing?  This dress is made of a front and a back.  I created the pattern by tracing a very simple knit dress that Lu owns.  I added a seam allowance, and made the bottom slant to one side.  If you don’t have a simple dress like this, no worries!  Take a tank top and just extend the length downward in a very simple “A line” fashion.   Make sure that the “stretch” of your fabric is going side to side instead of up and down.

I cut out two 3 x 28 inch rectangles to make a very simple ruffled sleeve.  There isn’t really a need to stress about the length of these pieces, as you’ll be using gathers to adjust them to fit the opening of the arm hole.

The next piece you will need to cut is the diagonal sheer that will go over the front of the dress.  The ruffles will attach to this piece.  Place the yard of sheer fabric over the edge of the dress at an angle and cut to make it fit the edges of the dress front.  Then set it aside.

Now we need to cut the ruffles.  I cut 1.5 yard coordinating sheer cut into strips (along the longest part of the length) each about 11 inches wide. When you fold each strip in half they are about 5.5 inches wide.  I was able to get enough for 5 ruffles–3 on the front and 2 on the back.  We now have all of the pieces ready!

Now that we have all of our pieces cut out, it’s time to start sewing.  Fold under the raw edges of the neckline and sew, using a stretch stitch since the fabric will stretch as your child puts it on.  Repeat for the back side of the dress.

Then, placing the right sides of the dress together, sew the shoulder seams together.

Gather each of your sleeve pieces. Next adjust the gathers so that they fit the opening of the arm hole.  Now pin in place, then sew. When you are finished it should look like this.  Repeat with the other arm hole. 

Now we’re going to add that big sheer piece to the front and the back.  Using a stretch stitch, attach the big sheer piece to the front and the back at an angle. Then set it aside. Now you can gather up all of the ruffle pieces.  In order to do this fold the pieces in half and sew a gathering stitch  along the top edge.  Now adjust the gathers to match the top of the dress–where the sheer piece is attached–and pin in place.  Sew to attach. 

For the top ruffle sew through the sheer and the bottom dress layer.  For the rest I attached the ruffle only to the top sheer fabric.

After you have attached the ruffles to the dress front and back, it’s time to sew up the side seams.  Place the right sides of the dress together, and sew up the side seams, through the sleeves.

That finishes the dress!  Now it’s time for the umbrella. I took 1.5 yards of sheer fabric and draped it over the top of my umbrella.  I used ribbon to tie it to the top of the umbrella.

Then I cut around the edges with scissors to trim the sheer fabric.

Next, tie the boas to each end tip of the umbrella, using small ribbon or yarn.  Also tie pieces of ribbon-about a yard each-to each of the tips of the umbrella. I wound my LED lights inside of the umbrella.

That’s it!  Pretty simple right?  I really love how this turned out!

Happy sewing (and Halloween!!) everyone!


blog contributor Jill

You can follow Jill on her blog (, on instagram, on pinterest, and on facebook.


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Check out these other gorgeous (and simple) costumes ideas that you can make today:


Make a Quick & Easy RAIN CLOUD COSTUME…for all ages!

DIY Mermaid Costume…with a REPOSITIONABLE Fin!



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Hi, I'm Ashley

Hi, I’m Ashley—the DIY-enthusiast behind this crazy blog!

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