Ginsu knives are well-known for their longevity and their durability. They first gained popularity in the late 1970s with a series of commercials showing the knife cutting through tin cans, nails and radiator hoses. The knife then cut through a tomato and created thin slices that many other knives could not replicate. The Ginsu knives have a lifetime guarantee and are not supposed to need sharpening under most circumstances, but they can be sharpened when necessary.
Lubricate the surface of your sharpening stone with either water or honing oil, depending on the type of stone you are using.
Angle your Ginsu blade against the surface of the stone so that the edge of the blade is at its bevel angle to the stone. The bevel angle is the recommended angle that type of blade requires to be sharpened optimally. Your knife set should have the bevel angles listed or you can link to the chart in the Resources section.
Run the blade across the stone from the hilt (the part of the Ginsu blade closest to the handle) to the tip. Slide the blade across the stone in this fashion 10 to 20 times.
Flip the blade over and repeat the process on the other side of the blade.
Repeat as necessary until you achieve the desired sharpness.
Wipe away any remaining oil from the stone and from the knife blade with a rag.