I wanted a devil costume that didn't require wearing makeup. So, I put this homemade costume together for a Halloween party a couple of years ago. It is very versatile and I was even able to wear it to work.
I found the horns at a local fair. They are made of fimo clay and originally had a string running through them. The string tied around your head and made for a cute devil horn look. I knew the string would look hokey for the type of look I wanted. So, I cut it off and bought a small piece of red modeling clay from the hobby shop. I stuffed the clay in the holes and smoothed it out. Then I used a red Sharpie to blend the color.
I used spirit gum to attach the horns to my head. Spirit gum works great for these type of applications. The trick is to spread it evenly then tap the horn (or whatever you are attaching) against your skin until it becomes sticky and stringy. Then hold it in place for a few minutes until the spirit gum solidifies.
If your spirit gum did not come with a solvent (it should have), you can use a simple mineral oil to dissolve the spirit gum when you are ready to remove your costume.
The contacts were an essential part of my costume. I wanted my costume to have a realistic look and this seemed the best way to do it. Contacts can be VERY expensive and they come in a wide variety of designs. If you have the money, there are some really nice hand painted costume contacts that can be worn long term. I didn't have the money for that, so I found some online that were less expensive that were designed for limited usage. They are still good quality but not something you want to be using day in and day out. I went for a red and yellow cat eye effect so it would be really obvious I had them on and the colors matched my horns.
If you don't own contacts or know how to put them in like me, find a friend who does and ask them to help you get used to putting them in and out. I have an almost uncontrollable blink reflex and it took me quite a while to get them in the first time. I was glad I practiced several times before trying to put them in before the party. It would have been very stressful to be getting later and later for a party while trying to get those things in my eyes. Even with practice, I still had to budget 15-20 minutes for putting in the contacts. Once they were in though, I got used to them quickly.
Last was the fangs. There are several brands of fangs available that you can mold to your teeth. I picked up a pair at a local costume shop without any trouble. They come with a mix that you blend and then fill in the hollow part of the fang. Then you press that against your dry tooth. Hold it there until it hardens (about 3 minutes) then pull it off and use fingernail trimmers to clip off the excess molding material. After that you can pop the fangs on and off your teeth easily and they look very realistic!
What you do with the lower half is up to you. Just about anything you put on will look scary now. I wore a dress shirt and tie to work and frightened plenty of people. It was a lot of fun!
This devil costume has patterns for the cape, tail and horns. It's a super inexpensive costume idea for a little boy or girl.