The technic I use, and it gives me good results, is as follows:
Place the silver on the steel block and position the stamp at
the desired place.
Tap the stamp with a hammer or heavy mallet, and then,holding
the stamp in the same place, tilt the stamp slightly to the
"North" tap again, tilt to “E” tap again, tilt to the “S”, tap
again, and finally,tilt to the “W” and tap. I find that this
procedure gives a better result then attempting to hit with a
heavy blow just one time.
I then place a piece of lead sheet on the block, turn the silver
piece over so that the shadow of the stamp mark that results on
the reverse side is uppermost. Now , with a light touch, planish
out the reverse of the stamped area.
Hope works for you. Joe Dule