many people clip the fingers off the fan leaves to prevent moisture loss. I don't have experience cloning in rockwool, I use rapid rooter plugs.

My procedure is:
sterilize sharp blade
find appropriate growth shoot around mid-plant height
take cutting and immediately put in a dish of PHed water
I then take the cutting and make a 45 degree cut about an inch above the original cut
place the nexly cut shoot in a DIY DWC bubbler with a weak rooting and growth solution.
put in humidity dome that has some ventilation
mist dome and rooter plugs NOT the cuttings

hope that helps