Justin, it kind of depends. If I have like a chalice coral of zoa I usually just take, a pliers or bone cutters and cut the "plug" part of the disc and put some thick (gel) super glue blob on the bottom of the disc then place it on the rock you want it on and hold it for about 10 seconds and let it go and they usually stay put. The coral itself will grow over the plug and you won't see it anymore
If i have like an acan coral that usually has a skeleton I break it of the frag plug and glue it directly to the rock. If I have an SPS that has not encrusted to the rock I break it off and direct glue to the rock as well. Good luck!
