They are fairly easy to
frag and can be cut like any other coral. The important thing is be sure the tool you use is very sharp so the cut is smooth and clean instead of tearing.
Once cut away from the plug, you will need to attach it to the desired rock. This can be done with a loosely fitted elastic band, covering with veil material, wedging between rocks or using a unflavored toothpick. Just be sure it's in moderate flow and you run carbon to remove the coral toxins it will emit. Water changes at a few days intervals wouldn't hurt either.
It will remain dormant for a time after it's cut but should be back to normal after a short while. I would also put the "plug" back into the tank. For the most part andything left behind should grow into a new coral. You can either
frag it again in a few months or sell it.
Cheers
Steve