I use a small pocket knife and work very slooooow and easy.just scrap from the spur to the bone,you can ring around the spur with th knife,("don't cut hard or deep"

then you can use fine steel wool to polish.clean out the holes in the bone to run your,leather or small chain through.I saw a some spurs the had put Gold leaf on the bone(not the spru,just the bone) it looke real good.
I am not a hunter I am a whitetail population reduction specialest
remember keep your back to the sun, your knife sharp, and your powder dry.