jklink

You can use antler stain or antler wax. Van Dykes Taxidermy sells some online for a reasonable price. You can pick the shade of darkness for both the stain and wax. In my experience, the light color does a good job and when you need it darker, just apply another coat. Make sure when you stain them, to have the skull upside down so you don't get any drips on your nice white skull.