If it's dry rock ie: Pukani, make sure it's as clean of organic matter as possible. If you are using Reefsaver or another mined rock, rinse it well to remove and silt and other debris and place it in the tank. Just know that you may get a small diatom bloom depending on how much you add. If you have space in your sump you can put it in there for a couple months then move it to the display tank. Now if it's cured live rock inspect it closely for unwanted hitchhikers like aptasia and such. If you see anything like that on it, let it sit dry for a few days to kill off everything on the surface, the interior of the rock will stay wet long enough so the bacteria in there won't die off. Scrape off any organic material as best you can and place it in the tank, however a QT tank would be better to aid in removing any now dead organic material.