Step-by-Step Instructions for Halloween DIY Unicorn Costume:
Halloween is coming; are you and your kiddos ready yet? As many of you know, I’m into DIY Halloween costumes that are easy to make, not to mention cuter and more budget-friendly than store-bought costumes. So when eight-year-old Kimmie decided she wanted to be a unicorn last year, I decided it was time to come up with an easy unicorn costume tutorial that was fast as well as easy on the wallet.
And given her age, I knew that it also had to be a more “realistic” depiction of a unicorn than the piles of rainbow tulle you often see in ready-made unicorn costumes for preschoolers. Something more sophisticated for my nearly-tween Harry Potter fan, since that was where she got her costume idea.
The resulting DIY unicorn costume took me maybe 2 hours to make total, and cost me less than $10 in supplies. Getting what I needed at the secondhand crafting supply store definitely helped. But even if you bought all the supplies new, you’re still looking at maybe $20 max.
This assumes that your kiddo already has an appropriate-colored long-sleeve shirt/tunic/dress and leggings to match, plus a basic headband and a belt. Some appropriate sneakers to go with the outfit are also a good idea. In our case, I could have scored all these secondhand at one of our fall children’s resale events for under $10 if we’d needed to, or one of our local thrift stores.
There is a tiny bit of hand-sewing in this costume, but don’t let that scare you off! Most of it involves cutting and knotting, with the occasional ironing. I’ve broken it down into tiny step-by-step instructions for a sophisticated unicorn look that’s perfect for your school-age kiddo, who’s too “big kid” for those ready-made rainbow tulle creations.
What you’ll need:
From your kiddo’s wardrobe (or hunt at your local thrift store if needed):
- Light gray or white long-sleeve Tshirt
- Leggings to match Tshirt
- White or light gray socks
- Sneakers – bonus if they are silver, white, sparkley, and/or reflective (In this case, Kimmie wanted her unicorn costume to have purple hooves, so I got her some purple sneakers for $2 at a fall children’s resale event)
- A belt, preferably light-colored
- A headband – one of those plastic C-shaped ones with the teeth (to help hold it in place) works well
- Optional: knit gloves that match or coordinate with the sneakers (the gloves and sneakers together are your child’s “hooves”)
From your local source for craft supplies, or your own stash:
- Some combination of white, light gray, silver, and/or silver-thread-run-through yarns
- One rectangle of white, light gray, or cream-colored felt, plus a few scraps of a darker color (for horn/ears)
- Fiberfill, cotton balls, fabric scraps, or old pantyhose (for stuffing the horn)
- Needle and light-colored thread (for minimal hand-sewing)
- A few scraps of double-sided fusible interfacing, for attaching inside of ears to main part of ears (this is optional, but makes things easier if you already have some on hand)
- Optional: silver ribbon or mesh, silver bead accents, etc. These are things I grabbed at our local secondhand craft-supply store when I was hunting for yarn, and they definitely added nice finishing touches to the horn, mane, and tail.
- A ruler, to help you measure and cut the string
- A small lanyard clip or a large safety pin, for attaching the mane to the headband
- A ring approximately 1 inch in diameter (i.e., an old keychain ring) – ring needs to be big enough to easily go around the belt you plan to use
- Optional, but a good idea: some hair clips, bobby pins, or small barrettes to help secure the mane in place and keep it from pulling the headband backwards off her head while she’s out trick-or-treating
For the horn:
- Fold one corner of the felt down to the opposite edge, forming a square shape. Cut off the excess at the bottom and set aside for the ears.
- Starting at one edge, roll the felt square into a cone shape, with the point being one of the corners of the square. Using the needle and thread, run a stitch up along the outer edge of the felt to hold the cone in place.
- Stuff the horn firmly with your stuffing material. Then lay the topside center of the headband across the middle of the open end (in a line with the finger you see in this photo), so that the top is facing the stuffing and the teeth on the underside are facing away from the stuffing. Fold the flap over the underside (teeth side) of the headband and sew the horn loosely shut, around the headband.
- If you have a mesh overlay or a silvery thread to twist around the horn, add this next. Once you’ve wrapped it around your horn, baste in place with your needle and thread as needed.
For the ears:
- Cut your leftover felt strip into half the short way, so you have two not-quite-square rectangles. Fold one in half the short way again, and cut a curve from the bottom edge corner up to the top folded corner to make an ear shape. Using that first ear as a stencil, cut the other felt rectangle into the same shape.
- Using your scraps of darker felt, cut two smaller versions of the same shape for the inside of your ears.
- Place a layer of backing paper, clean paper towel, or a clean rag on your ironing board, then the darker parts of the ears, then the fusible interfacing with the paper backing side facing up. Iron the interfacing onto the backside of the inner ears. Then cut out the inner ears from the interfacing and peel away the paper backing.
- Place the light-colored ears on the ironing board. Center the dark pieces on top of them, with the interfacing-covered side facing down (touching the light ears underneath). Cover with backing paper or a pressing cloth, and iron until the inner ears are fused onto the lighter main ears. (If you don’t have fusible interfacing, you can sew the inner ears into place using light-colored thread and a whipstitch around the edge, but your stitches will show.)
- Now take one ear and fold it in half, the same way it was folded in half when you first cut the large ear shape from the rectangle. Sew the ear together along the bottom seam, then pull the side edges apart to make the ear three-dimensional.
- Sew one side of the ear to the base of the horn, facing forward.
- Repeat the entire process with the other ear.
For the mane:
- Have your child put on the headband. Lay one end of your yarn against the top end of the headband, and measure down the back of your child’s head to the nape of her neck. Measure the length of the string; for Kimmie, this was about a foot (12 inches/30 cm). Now cut 2 strands of the yarn to a length that is twice as long, and secure them to the base of your lanyard clip. This is the base of your child’s mane.
- Add 2 inches/5 cm to that doubled length; that is the length of each strand of the mane. (The extra little bit allows some length for knotting.)
In our case, this just meant wrapping the yarn around both ends of one of the girls’ rulers, which was slightly longer than 12 inches per side.
- Depending on how many colors and types of yarn you have, and how thick it is, cut lengths of yarn in groups of 2-4 strands for each section of the mane. (Because I had a lot more of the charcoal yarn than the silver-white yarn, I cut 2 pieces of charcoal for every 1 piece of silver-white.) You’ll find it easier and faster to wrap/cut a lot of pieces of yarn at once, instead of doing each one individually, then knotting, then cutting more. Start by making enough yarn for 10 clusters, and then check your progress against your child’s head.
- Starting at the lanyard clip and working your way down, tie the center of each cluster around the base strand, starting at the lanyard end and working your way down the base strand. (Tying the mane strands on in clusters will save you time – fewer knots!
This will be much easier if you clip the lanyard onto something, so you have some tension to the base strands while you’re tying. (I slipped mine around the pocket-clip part of a pen that I held between my legs while I worked.)
- Once you’ve knotted the initial 10 clusters around the base strand, check the length of your mane against your kiddo’s head. Cut and add more knotted clusters if you want the mane strands to hang down longer.
- Once the mane is as long as you want it, grab the ends of the base strand and knot them together with the last cluster of strands, so the end of the base is secure and your clusters won’t slide off.
- If you have bead accents, slide a few strands into some of the knots in the mane.
- Clip the lanyard onto the back of the unicorn horn when your child is ready to wear it. Secure strands of mane to your child’s hair as needed, going down the back of your child’s head, so it stays in place instead of swinging off to the side.
For the tail:
- Have your child put on the belt they’ll be wearing, and figure out how long you want the tail to be based on how tall they are. For reference, Kimmie was about 4 ft 4 in tall (132 cm) last October, so that meant a tail about 18 in (45 cm) long.
- Now DOUBLE that length. This is how long you’ll want to cut each strand of the tail. In our case, this meant 3 feet (1 yard, or about 90 cm) per strand.
- Measure and cut however many lengths of yarn you want for the tail. My goal was to use up all our leftover yarn, which meant about 100 lengths total.
- Thread the yarn lengths halfway through the ring you’re using for the tail. Repeat until the tail is as full as you want. Secure by wrapping a length of yarn several times around the ring-end of your yarn cluster, then knot securely.
- If you have optional bead accents, again, weave in several strands as desired.
- Thread the ring through the non-buckle end of the belt, and your unicorn tail is ready to wear!
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