Reply by uffitze

I learned pretty early on how to do it without a honing guide.

The trick that I learned is to hold the chisel/iron rigidly in your right hand on the bevel, and then use your left hand in a sawing type of motion to push the chisel/iron back and forth on the stone (or sandpaper). Again, your right hand is simply holding the iron/chisel on the bevel, and the left hand pushes it across the medium. Note, that by doing it this way, motion is along the cutting edge of the iron/chisel, and you are much less likely to rock on the bevel (and therefore screw it up).