There are many ways to carve a ham. I find the following one easiest to remember and it ensures that every slice gets a little fat. If you are right-handed, place the shank of the leg to your left. Slice vertically down through the fat, about two-thirds along the leg from the shank end. Stop when you meet the bone. Slice another cut parallel to the first, but at a slight angle, making a thin wedge-shaped slice that can be levered out. Now slice out thin wedges, first from the right side, then from the left. When you are no longer able to slice like this, turn the ham over and slice the underside, cutting across the grain of the meat as much as possible.
Many people prefer to slice right across the meat, lifting off 90% of the fat with the first slice. I don’t agree with this method, not only because it robs all but the first few diners of a little fat with the lean, but because, if the ham is to be stored and used again, the fat will keep the meat moist and sweet.