Is there live tissue at the location you would like to cut it? If so, it will take a week or so to heal. Also know that if your are maintaining a healthy reef environment, those things grow like weeds.
In my experiance, most euphyllia have very porous skeletons and they are really easy to cut. If not with a simple razor blade rocking back and forth, with a set of diagonal cutting pliers.
Be sure to gently shake the coral around in the water before you remove it. When it’s tentacles are full of water the weight is sufficient to tear the flesh outside of the tank. Also, they can tolerate being out of the water for a considerable amount of time with no ill effects. Do be prepared before you remove it from the tank, have all the utensils you think you will need laced out but don’t be in a rush when you are fraging it, Take your time and do it nicely.
Happy reefing and may chance ever be in your favor.