Usually done by hand holding the shaped and sharpened graver.
You can use 600 grit wet/dry paper over a hard surface.
Or you can use a stationary diamond lap or EZ lap.
My method is to hold the graver with the bottom lift and clearance area slightly raised with the point in contact with the abrasive surface with light down pressure.
I then move the point against the abrasive as if I was trying to write a letter Z on the abrasive.
Give it a try. Works for me, your results may vary.
Also after sharpening the graver we would also jab the tool in a block of wood to remove any residual bur remaining from sharpening. Does that also qualify as dubbing the point?
Besides adding that tiny steeper face area to the point (I do so on a black Arkansas stone) you can round the bottom of the tool just in the heel area by drawing it back across the abrasive while rolling side to side.
The stabbing of a newly sharpened graver into the end grain of a piece of hardwood is effective in removing any rolled-over metal edges (wire edges) that remain connected to the graver.
Stabbing the end grain is also thought to apply a slight polish to cutting surfaces.
Some engravers also allow a little oil to soak into the end grain to add a slight lubrication of the graver.
Give it a try and see if you like it.