The process is always the same whatever the stone is:
you must always go towards the edge as if you were going to cut a fine slice of the sharpening stone. Do not forget to use water.
The position of the stone is up to you, try several ways.
1) To make it easier, fix the stone on the table or a bench with a clamp or just put it on a wet kitchen-roll paper (to prevent it from slipping).
In that case, just take the right angle (15° to 20°) with all the body push it with the point forward as if cutting a slice of stone.
A few strokes in one direction and about the same number in the other for a symmetrical work.
2) You can also hold the stone in one hand, the knife in the other and cut a thin slice of stone ; in this case, the knife will rather slide from the handle to the point.
It's a very convenient way when you haven't any room for the stone, but the angle of the edge is more difficult to keep.
The best thing is to try, to find your own way.
3) If the knife is particularly difficult to sharpen, you can also draw circles (this method can often be seen) but in this case, you must press the knife on the stone and stop pressing when you are far from the edge (always the same rule: go toward the edge which avoids the wire edge).
As usual in France there's an exception to the rule when you use a water-mill.
In this case the best way is to have the edge facing away from you, for two reasons:
-Less danger for you, if you drop it
-and for the knife if you press too much accidentally.
Anyway the work by a mill is rough, the wire edge will be taken off on a stone.
The water grindstones you can find in a shop are usually designed to be used with the edge facing away from you than facing you.
For a super finish and a razor edge, sharpen the knife with a very small angle (12°) a thin stone then rub on a strop with a razor paste (as our grandfathers used to do).
and must be spread on an old thick piece of leather (from an old bag or belt).
Then rub your knife on it, with the edge facing away from you, on both sides, in this case.