This process assumes that the horn has already been separated from its bone core.

1. Finding the horn: Try to find a horn that has relatively few flaws in it. Keep in mind that no horn is perfect. A lot of work will have to be done to make even the best raw horns presentable. Choose colors that will complement the pigment you will be using later.
2. Clean the horn: The inside of the horn must be cleaned and sanitized before any work can be done. First, you should sterilize the inside of the horn with a strong mixture of bleach and water. Let it soak overnight outside or in a well-ventilated area. Neutralize the bleach with vinegar. After bleaching DO NOT USE AMMONIA. Then wash the inside of the horn with soapy water and a scrubbing wire brush. Be sure you reach all the way down inside the horn. with course grit paper. Be careful to remove only the blemishes and not to sand to long in one spot; you want to retain the natural curved surfaces of the horn. If you do not have a power sander you will have to sand by hand. If the blemishes are extreme a file or sharp knife can be used to cut them away. To remove major blemishes you may go across the grain of the horn. This will speed the sanding process. Make certain that the following sanding are done with fine and then ultra fine grit paper. Final sanding should be done with an ultra fine flap sander or a polishing cloth. You do not need to sand the entire surface or the horn; leave the top portion, which you will later cut away.
3. Cutting the top: Cut the top of the horn off with a fine toothed saw. A hacksaw will probably suffice, but a band saw will be preferable. Try to cut the top off as level as possible. Sand the raw edge smooth with ultra fine grit paper then a polishing cloth.

4. Cutting the design: Trace or draw the desired design onto the horn. Remember you are transferring a flat image onto a curved surface and will have to compensate. Carbon paper will work well for this.

5. Etch the design: Use a stylus, nail, or a strong pin to scratch the design into the surface of the horn. A dremel tool or carving knife can be used for deeper images. Be very careful. A mistake is best remedied by finding some way to incorporate it into the overall design rather than trying to sand it out.
6. Pigmenting the design: Use pigmented wax or water based ink to fill in the design. Use caution with ink that it does not flow freely into small cracks and crevices in the surface that you did not notice before. If ink is used, carefully sand off the ink remaining on the surface.
7. Wax the outside: Warm the horn so that it will take the wax more readily. Smear the wax across the surface of the horn. Beeswax works well for a shiny finish. Shoe polish will also work if spread very thinly, but it will change the color of the horn slightly. Buff the horn with a rag to even out the coating.
8. Treat the inside: Again, beeswax can be used. Do not use this method if you intend to drink hot liquids. Salad bowl finish can be found at unfinished furniture stores and also works very well. For those with authenticity concerns, no, it is not period. But it is made from natural mineral oil and spirits. Hot and cold liquids of varying strength can be drunk from the horn then. To use the finish, first heat the horn, and then apply finish liberally to the inside with a brush or rag. Be sure to coat the entire interior. Dump out the excess. Hang the horn in a well-ventilated area with a fan blowing up into the horn for 24 hours. The finish will require 72 hours to cure completely; then it will be safe to drink from.