As you hone your skills with kitchen knives you can also hone your skills with the honing rod. Doing so will extend the sharpness of your knives. Yet, what's going on when we hone? Why do we do it?
Each cut a knife makes wears on it's sharpness just a little bit. It becomes a bit more dull, unaligned. You think of it as microscopically folding over the cutting edge like a visible nick or a ding might. There could be lots of little folds in what once was a very straight edge. To restore sharpness a knife can be honed or straightened again.
A honing rod is typically round and made of a material harder than your blades so it can exert force on the blades. Most rods are made of a steel or ceramic and they will work to re-align the metal on the cutting edge of your blade but stop short of removing material.
Some rods are coated with harder materials (like diamonds) and designed for sharpening (things like serrated knives). The key difference between honing and sharpening is that when you're honing you're realigning the edge that is already present on the knife. Whereas, when you sharpen, you're removing material to create a new cutting edge.
To hone, run your knife along the edge of your rod at a matching angle to the knife's cutting edge (more about knife angles). German knives will have a slightly larger angle by a few degrees than Japanese knives. Largely you can eye this up when honing. Hold the knife at that angle for the whole of your pass on the rod. Start at the top with the heel of the knife. Run the knife continuously until the tip of the knife reaches the bottom of the rod. Do so equally on both sides. Either all on one and then all on the other or alternate. We prefer holding the end of the rod on a cutting board.
Hone often and extend your knives sharpness. Consider honing once a week or more often if your knives see a lot of action. However, if the knife you're working with is "rounded out," it no longer has material to straighten at the microscopic level, or the knife has nicks and dings in its cutting edge, then no amount of honing will better the performance of the knife. It's time to sharpen.
Interested in sharpening? More on how to sharpen a knife available here.