Whether you’re creating horns for a Tiefling, gijinka, devil, or some other horned character, you want to make them durable and lightweight so they last the whole convention without pulling your wig off of your head. The process is pretty much the same whether you are creating small oni horns or large, curly horns.
This tutorial will take you through step by step how to design a mock-up of your horn, what materials to use, and how to easily paint your horn in a realistic way. My design is creating large ram horns, but you can use the same technique for whatever shape you need to make.
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Most of these supplies are the basics you’d need when working with EVA foam. So, if you’ve ever worked with it before, you probably have most of these in your cosplay closet. Clay foam might be something new to work with, but it acts similar to any other kind of clay, but dries as the same material that EVA foam is made of.
The supplies you will need to follow this tutorial include:
- Aluminum foil (optional). You’ll need this if you are creating your own pattern for your horns.
- Plastic wrap (optional). This is only needed if you are creating your own foam pattern.
- Duct tape (optional). Duct tape is also only needed if you are making your own pattern.
- A sheet of EVA foam. I recommend 4mm or 6mm EVA foam to keep the horns as lightweight as possible. You can also use craft foam.
- Sharpie or writing utensil. Make sure it can easily write on the foam surface.
- A sharpened razor. I also recommend using a knife sharpener to keep the blade sharp between cuts.
- Contact cement. You can also use super glue or hot glue, but I find that contact cement works best.
- A heatgun. Used to fine-tune the shape of the horns.
- Sandpaper. I use a rotary sandpaper tool called a Dremel to make sanding a little easier.
- Clay foam (optional). This is used for giving your horns natural-looking ridges. It’s not necessary if you are creating horns with a smooth texture.
- Primer. Mod Podge works well enough, but you can also try a flexible primer such as Flexbond.
- Paints. Acrylic paints or flexible paints work well. I am using black and a metal grey for the effect on these horns, but choose whatever colors you need for your costumes.
- Hairband or hair clips. This is for attaching your horns to your hair or wig. Headbands are the easiest to use, but hair clips mean you’ll have more flexibility in where you place your horns on your head.
Step 1: Find or make a pattern for your horns
The first step for any EVA foam project is to get your pattern pieces ready. These are the separate, flat pieces that you’ll cut out and glue together to make your 3D horn shapes. You only need one set of pieces to make horns (the pieces for one of the horns). If you have the pieces for the left horn, you can flip them over to get the pieces you’ll need for the right horn.
There are two ways you can go about getting a pattern for your horns. The first is to purchase a pattern from someone who’s made them. It’s the same idea as purchasing a clothing pattern for the fabric parts of your costume. Kamui Cosplay has some great horn patterns that you can download and print so that they’re ready to use.
If you don’t want to buy a pattern or none of them work for your desired horn shape, then the other option is to create your own pattern. For this step, you will need:
- Aluminum foil
- Plastic wrap
- Duct tape
- A sharpie
- A pair of scissors
- Start by crumpling sheets of foil together to form the shape of the horn you want. Remember, you only have to create one horn because once you have the pattern pieces you can flip them to create the other horn.
- Wrap the foil horn in a layer of plastic wrap. This is to keep the duct tape from sticking to the aluminum foil.
- Layer strips of duct tape over the plastic wrap. You want it to be snug, but not too tight. This way you won’t change the shape of the horn underneath the tape.
- Use a sharpie to draw on lines that you will cut along to create the pieces of your pattern. You want to create pieces that will lay flat when they are cut. For horns, I will generally separate them into four sides.
- Draw registration ticks on all of your lines. Simply draw little lines along the edges of all of your lines. These are going to help you line up the pattern pieces correctly when you are constructing your horns later.
- Label all of the pieces. This way you won’t get confused about which piece goes where. I also like to take a picture of the labeled horn before cutting it so that I can go back and reference it when constructing the horns.
- Cut out the pattern pieces. Once they’re cut out you can peel off and discard any excess plastic wrap.
- Trace the pattern pieces onto plain paper and clean up the lines. Don’t forget to also transfer the registration ticks and labels to your paper pattern.
Step 2: Cut out your pattern pieces in EVA foam
This step is pretty simple. All you’re doing is cutting out the foam pieces that will end up being the base of your horns.
- Trace your pattern pieces onto the EVA foam. Make sure to include the registration ticks and label all of your pieces as you go.
- Use a razor to cut the foam pieces on the inside of the traced line. Cutting along the inside of the line ensures that the foam pieces are the same size as the pattern pieces. You also might want to occasionally sharpen your razor so that you can have cleaner cuts.
- Taper the edges of the horn tip. To help the horn come to a point, you’ll want to taper the side of the foam inward on all the pieces that make up the tip.
- Flip the pattern pieces over and repeat for the second horn. Make sure to label which pieces go to the right horn and which go to the left.
Step 3: Glue your pieces together
Now it’s time for the fun part! In this step, you’re going to glue the pieces together so that you’ll have the basic shape of your horn. I like to use contact cement for this because it works well with foam and easel peels off of my fingers, but you can also use superglue if that’s what you have available.
Make sure to do this step in a well-ventilated area because the fumes from the contact cement can be toxic.
- Add contact cement to both edges that you’re gluing together. Wait 5-10 minutes for the contact cement to get tacky. If you don’t wait, the glue won’t work properly.
- Starting at the tip of the horn, connect your first two pieces. Slowly roll the two edges together, making sure to match the tick marks on either side. Push the two edges together to make sure the contact cement will hold everything together. The foam can stretch and compress a little to help you get it into the correct position. The base of the horn should match up, but if they’re not exactly right you can clean that up later.
- Using the same method, attach the other pieces until you complete the shape of the horn. Once the horn shape starts to close up, it gets a little tricky. Always start at the tip of the horn so that you have more space to maneuver your hands on the open base.
- Wait to attach the base of the horn until a later step. It’s easier to sand and paint the horns when you can still stick your hand through them, so I recommend waiting until the end of this tutorial to attach the base piece of the horns.
Step 4: Fine-tune the shape and heat seal
Now that you’ve got the basic shape of your horn, you’re already 80% of the way done. All we really need to do now is clean it up and add some details. To start with, we are going to use heat to make the shape of the horn exactly what we want. This will help make sure it curves correctly and keeps its shape. Using heat will also help to seal the foam which makes it easier to prime and paint in the later steps.
Because the plastic foam can be toxic when heated, make sure to do this in a well-ventilated area. It’s also recommended that you wear a face mask to avoid inhaling the fumes.
- Using a heatgun, gently heat up the plastic foam horns. Don’t keep the heat pointed at one place for too long or the horns will start to melt.
- Gently bend the horns and keep them in the desired position until the foam cools. I found it useful to have one hand inside the horns to keep them from collapsing on the inside.
- Repeat as many times as necessary until the horns look right to you.
Step 5: Sand the seams
You have your horns and you’ve shaped them to perfection, so now it’s time to smooth everything out to make the horns look as seamless as possible. For this step, you could use good old sandpaper, however, I find it is much easier to use a rotary sanding tool, like a Dremel. It will make the process go much faster.
Like in the previous two steps, you want to stay in a well-ventilated area when sanding EVA foam. You don’t want to inhale too much of the dust since it is toxic. It’s also recommended that you wear a facemask and goggles to keep the dust from getting into your mouth, nose, and eyes.
- Go over each of your seams with the sandpaper or Dremel. This will help to smooth out the ridges that you might get when connecting pieces together.
- Once you’re finished sanding, brush off the dust. This way it won’t get in the way when you are decorating and painting. You can also use the heatgun to blow away the dust and melt any tiny remaining pieces.
Step 6: Add details
If you wanted smooth horns for your cosplay with no added designs and details, then you can skip this step and go straight to painting. But, if you want to make something like ram horns or dragon horns, you probably want to add details that will bring them to life.
To create organic shapes with EVA foam, you’ll want to use something called foam clay. This is a material that behaves similar to clay when wet. When it dries, foam clay becomes a material that works just like EVA foam that can be heat-formed, flexible, and lightweight. For my horns, I only used foam clay and some sanding to get the shape right. However, the are many different techniques for adding interesting or realistic details to your horns.
Some people will add decorations or details to your horn by using engraving tools, to etch lines into the horns. Or you can even cut out more pieces of EVA foam to add details that way. It all depends on what you want the final horns to look like. So, don’t be afraid to experiment and find the techniques that will work for you and your project.
To use foam clay you will need water to help the clay adhere to your foam horns. It’s also useful to have a razor to score the foam and the clay to make it stick better.
This is what I did with my horns. You can follow the technique if you want a similar result:
- Start by taking a small amount of clay and rolling it into a log. Check to make sure it will fit around the horn near the tip.
- Score the foam with a razor on the spot where you will be adding your clay. Scoring is a technique where you make shallow cuts in the foam. It’s a technique used with clay molding to help the clay stick.
- Add water to both the clay and the foam surface, then wrap the clay around the horn. I just use my fingers by dipping them in water and wiping the foam and clay.
- To create the ridge effect, pull the clay down along the horn with your fingers. Keep the upper edge of the clay piece intact.
- Repeat the process to form another ridge below the first. Make each ridge toward the base thicker than the last to create a more realistic effect. I added six ridges to each of my horns, but you can easily add more or less depending on the effect you are going for.
- When you are finished with your design, allow the clay to dry for 24 hours. When it’s dry, it should feel just like foam.
- Sand any areas that are too uneven. I’m not always neat with the clay, so I always have to go back with the Dremel to sand down areas that are too bumpy and lumpy.
Step 7: Prime and paint the horns
Once your horns look exactly how you want them to, it’s time to paint! Just like adding decorations, there are countless ways to approach painting horns. Some people will want to go in with tiny brushes to make meticulous designs, whereas others will only need horns in one solid color. This is another area where you can absolutely feel free to play around until you find something you like. If you mess up, you can always paint over your mistakes and try again.
Regardless of how you paint your horns, you always want to prime them first. Using a primer helps to seal the surface of the horns. It will keep the paint from seeping in so you need fewer layers of paint and the color won’t look faded. My favorite primer to use with EVA foam is called Flexbond, but even something like Mod Podge will work well for these.
This was my technique for painting the horns, so if you like how they look you can follow these steps:
- Prime the horns. I used two layers of primer to make sure it got into all the little crannies of the horns. Then I used a slightly watered-down primer for a third layer to help remove the appearance of brush strokes.
- Paint the horns black. My base color for these horns is black, so I added two layers of a solid black paint. In this case, I used Hexflex paint because it doesn’t crack when the horns are bent, but acrylic paint will work just fine.
- Use a sponge to streak grey paint along the horn. I dip the sponge in the paint and rub a thin layer on the horns. This creates a layering effect so you have streaks of grey on top of the black. It also ends up highlighting areas of the horns that jut out (like the ridges).
- Go back in with black paint. I didn’t want the horns to be evenly streaked with grey so I went back in with the black. I feathered black paint on the underside of the ridges. This did a better job at creating more variety and interest in the paint.
Step 8: Decide how the horns will attach to the wig
After all of your layers of paint dry, you have your finished horns! Now all that’s left to do is attach them to your costume. Remember those base pieces of horn that we left out of the third step? Now it’s time to add those inside the horn base so that the horn will keep its shape and not collapse when they’re on your head. I like to glue them about half an inch inside the horn so they don’t show at all (since they’re not painted).
Now you have a couple of options for attaching the horns. The first is to use a headband. This is probably the easiest method for keeping horns in place and it’s recommended for anything that is going to be very tall or top-heavy.
- Using a wig head with a wig on, put a headband on the wig and hold your horns in place how you want them to appear.
- Mark the headband so you know where to attach the horns.
- Glue the horns to the headband. Alternatively, you can cut little slots in the base of the horn and slide them onto the headband instead. This would give you more ability to adjust the horns later on.
Instead of using a headband, you could also use hair clips so that you can attach each horn to the wig independently and avoid needing to cover up the headband. I ran into a little bit of trouble when connecting the hair clips. First I tried gluing the clips on with hot glue, but the foam was too thin and the clips wouldn’t adhere properly. Instead, I ended up sewing the hair clips onto the base of the horns. I recommend using two clips for each horn to help them stay securely on your head.