Instead of sharpening a knife, a honing rod "trues" the edge of a slightly dulled blade. So how do you use it effectively?
A honing rod (also referred to as a sharpening steel), the handled metal rod sold with most knife sets, doesn’t really sharpen a knife. Instead, it “trues” the edge of a slightly dulled blade. Over time, the sharp cutting edge of a knife blade can turn to the side, making the blade seem dull. A knife that feels dull may need only a few light strokes across a honing steel to correct its edge and restore its sharpness without the need to run it through a sharpener. The honing process is also faster than sharpening a knife (about 1 minute to hone versus 5 minutes to sharpen) and doesn’t remove much metal from the blade.
To know if you need to hone or sharpen your knife, perform a paper test: Simply hold a single sheet of copy paper, place the blade against the top edge, and slice down, from heel to top. If the knife drags or catches at the paper, try honing the knife (see steps below) before testing again. If the knife still fails, sharpen it.