Going to a fancy dress party? Or wanting to be a little devil for Halloween?
Here's a quick and simple method for making some nice little horns.

Step 1: Materials and Preparation

The main material is sponge pipe lagging. It's used to stop water pipes from freezing in winter and is available at many hardware stores and DIY outlets. It's very cheap, I got a 2" diameter piece 3 feet long for £1.15 GBP (less than two dollars US).

If you are having difficulty finding this stuff you could use 'pool noodles' instead - just Google them.

Using a sharp knife, cut a section off as long as you want your horns. I cut a piece about 2 1/2" long (7 cms). Cut this in half, then in half again. Next carefully cut from the centre at one end to the edge at the other, repeat for all the lengths. This will leave you with 4 large triangular sections and 8 smaller ones. Enough to make 6 sets of horns!

Step 2: Carving and Sculpting

Take one of the matched pairs.
It is possible to do the next step using a sharp knife and sandpaper, but if you have a rotary tool (like a Dremel) it takes seconds.

Put a rough sanding drum in the rotary tool and sand away the top surface all around to reveal the 'grain' of the sponge. This will give a surface texture very similar to antler horn or old bone.
Try and keep the two horns the same general size and shape.

Once you pull off all the little bits of scrap material you should be left with a pair of nice cone shaped bits of sponge.

Step 3: Sealing and Making the Bases

Next we need to make the bases and seal the horns in latex. Normally I use greaseproof paper, an oven paper or baking sheet, tracing paper or wax paper to make my horns on. These are all non porous, cheap and readily available. However here I have used some black plastic sheet so you can see what's going on.

Liquid latex is available on ebay, from art or theatrical shops, or as a 'fabric glue' known as Copydex here in the UK.

Tape a piece of sheet to your bench. This will help to prevent the paper from 'cockling' too much.

Using your horns as a guide, paint a layer of latex on your sheet about 3/8" or 8mm larger than the diameter of the horns. Put a cocktail stick into the base of the horns to make them easier to handle and paint a layer of latex all over the upper surfaces of the horns.

The latex can be over painted once it as dried (gone transparent). We need three layers on the base sheet and three layers on the horns. Once the upper surfaces of the horns have had three layers and are dry enough to handle, remove the cocktail sticks and paint three more layers onto the bottom of the horns, allowing each layer to dry before adding the next. You can use a hair-dryer to speed up this process.

You should now have two horns completely coated in cured latex and two bases of dry latex as well. The latex will instantly bond with itself even when it's in this dry state. Just like an impact adhesive. Carefully push each horn down onto it's base on the sheet - it will instantly form a bond.

Run a small fillet of latex round the join on each horn to seal it, then leave the whole lot overnight to cure.

Step 4: Painting

Once the horns have cured overnight, we can start to add colours. Because liquid latex is mostly water, we could add colour directly to some latex and paint on another layer. This is a good choice if we want very robust horns we are going to use many times. The pigment becomes an integral part of the latex and then only needs a light over painting to finish. However for this 'ible we'll just paint over them.

Give them a light dusting with talcum powder or chalk dust (or French chalk). This will prevent them from accidentally sticking to each other and prepare them for paint.
The latex in this state will accept acrylic colour, face and body paint or make up quite well. I'm going to use some artists acrylic and hobby acrylic on mine.

Starting with some white at the tips, then some red, followed by some brown and black around the bases. You can apply the paint using a brush, sponge or airbrush as you wish.
Blend out the colours for a more realistic look.

Make sure that you leave the horns attached to their bases until you are actually going to fit them.

Step 5: Fitting

The horns can be glued in place using any theatrical adhesive. Spirit Gum, Pros-Aide or theatrical liquid latex will all do the job. I tend to use liquid latex since it simplifies the amount of crap I need to carry around with me.

The method is very simple. Using a sponge dab a very thin layer of liquid latex on to your victim (er model) where you want the horns to go. make the area of latex just slightly larger than the base of the horns. DON'T GET GLUE IN YOUR MODELS HAIR! It's painful and difficult to remove.

Allow the latex on your model to dry, then CAREFULLY peel of the backing paper from your horn and gently but firmly push it on to your model. just like before it will bond instantly. Gently smooth down the edges so that all the base is stuck down. Again give the bases a little talc to stop them feeling sticky, then use some make up foundation or face-paint to blend away the edges.