take the antler you intend to use ,lay it on its side on a table-top or work bench, any way lay it on its side , then take your bow tip-end lay on top of the antler and use a pencil to scribe the top surface of the bow tip for how ever long you want the tip overlays to be..then cut the excess off the bottom of the antler to the line and final sand to fit,, it should fit perfectly if you show the line after sanding..did any of this make sense? don't know how else to put it without showing you.. jp