DIY Skeleton Mermaid Costume

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Make a DIY skeleton mermaid costume with iron-on vinyl and a black dress to refashion. It’s a creepy cute costume that’s so fun!

My youngest daughter had a really hard time deciding what to dress up for Halloween this year. She kept asking to be what her siblings were or what her siblings dressed up in years past.

I wonder if she just couldn’t imagine something she hadn’t seen. I just started making a skeleton mermaid costume hoping she would wear it when it was finished. The verdict: SHE LOVES IT!

diy skeleton mermaid costume

I think adding a pink mermaid heart is was sealed the deal. She loves that there’s a touch of pink, and that it has mermaid scales like a mermaid tail!

skeleton mermaid costume diy

This is the first time she’s worn a maxi dress (that isn’t a dressup) and she loves feeling so grown up. You can see her watching her tail swish as she walks.

I refashioned a black women’s dress for this project, but if you can find a black maxi dress for little girls that will also work. Adding the iron-on vinyl makes for professional but easy details.

skeleton mermaid diy

I did some simple skeleton makeup on her face and she just loved it. She wants to do make up all the time.

I love making mermaid sewing projects like these:

skeleton mermaid costume

DIY Skeleton Mermaid Costume


supplies skeleton mermaid

Cut open the side seams of the dress so that you can open it mostly flat.

cut open sides of dress

Lay the sleeves on top of each other wrong sides together. Use a sleeve pattern or a t-shirt from your child’s wardrobe as a guide for the sleeve.

cut sleeves

Using clothing as a guide draw a straight maxi dress shape that goes out from the knee or upper thigh. I placed a pair of leggings and a t-shirt down as a guide to get the height and shoulder area right.

Only draw half of the dress.

draw dress shape

Fold the dress in half lining up all the sides and the middle of the pattern piece. Cut out the back pattern piece.

cut dress back on fold

Use the back as the pattern piece for the front. Then cut the neckline lower on the front piece.

cut dress front

From the remnant pieces cut a neckband piece. The neckband should be 85% of the neckline measurement and about 2 inches tall.

cut neckband

Use a cutting machine to cut all the pieces of the skeleton mermaid. I did white regular iron-on vinyl for the bones, and I did pink glitter for the mermaid heart.

cutting machine vinyl

Weed all of the designs.

weed iron-on vinyl

Use an Easypress to apply all the iron-on vinyl. Go slow to do it piece by piece. I measured the ribcage wrong and it came out too big. I just cut some of the outer edges off before applying it.

Layer the pink heart over the ribcage.

layer heart over ribs

When I did the arms I had to do the upper bones separate from the lower bones to get them right next to each other.

fuse iron-on vinyl

Sew the dress as you would a t-shirt. Since you reused the sleeve hem and the hem of the dress, you won’t need to hem anything. Just tack the sides seams at the hem towards the back.

sew dress together

Cut your tulle into strips that are 6 inches tall. Gather the tulle into one long piece. Pin it near the hem of the dress in a place where there is no iron-on vinyl. I pinned my tulle right above where the fin starts. I gathered enough tulle to go around the dress twice.

gather tulle pin tulle

Sew the tulle in place with a zigzag stitch. Use black so that the thread blends in the with the dress. I sewed while looking at the outside of the dress to make sure I didn’t sew on any iron-on vinyl.

sew tulle near hem

Turn the dress right side out, and it’s finished!

finished skeleton mermaid costume

If you make something using this sewing project, I’d love to see! Please share it on social media with the hashtag #heatherhandmade and tag me!

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oh so cute but to bony ahha…i thought it would be cute for my grand daughter she likes the mermaid and halloween ..so i thought she might really like it …thank you for all of your great ideas for the children ..i bet your kids love having a mom that can sew so well..wow..this is so cute..

So cute and creative! Great use of all the materials. It is a sure winner!