I cut mine off the leg by making a cut through the leg bone on each side of the spur. Take a sharp pocket knife and work the scales off starting at the base of the spur. If you have let them lay for a while and they are getting dry, heat a pan of water to boiling, turn it off and throw the spurs in for about five minutes. That will soften the scales and they will come right off. Run a pipe cleaner or similar through the bone to get out the marrow. Once dry you can brush on some peroxide cream and let them get white.
I string mine on a piece of rawhide shoelace, alternating, two spurs, beard, two spurs, beard...etc.