With a spiral slicer. The ham is put on a skewer and rotated slowly past a stationary blade parallel to its leading surface.
Some people have difficulty making clean slices of ham. Using spiral cut hams makes it easy to get clean slices.
they cut them with this special machine that cuts spiral things. including ham. ;p
wendell dunn invented the spiral ham technology
Sometimes some things are better off pre purchased but basically you want to cut through the meat at a slight (15 deg) downward angle starting perpendicular to the bone. start at the thin end working...