Clean your deer antler with a cotton ball dipped in rubbing alcohol. Use long, smooth swipes and make sure you cover the entire piece. No need to dry; the rubbing alcohol will evaporate in a matter of seconds after application.
Put on rubber gloves. Dip your antler piece into a 33-percent solution of acetic acid, available at most knife and leather artisan stores. This etching solution roughens the antler so it will take the dye better. Count off 15 seconds and remove the piece from the solution.
Dip the antler into a liquid mix of potassium permanganate for about 15 seconds at a time. Keep dipping until the antler reaches the desired color. Potassium permanganate will turn your antler to a burnished, rich brown.
Rinse the piece in cool water for about a minute. This neutralizes the dye and acid. Don't remove your rubber gloves, however.
Soak the antler in mineral oil for about 15 minutes. Remove it from the oil and rub it dry and clean with a clean, soft cloth.