well depends on how you do it - -
fish in, or fish out?
are you draining down the tank?
FILTER OFF!!!!
if fish in - scoop it in with cups, submerge the cup in the water slowly so the sand stays in side the cup, and keep pouring it into the same corner. then use your hand to "smooth" the sand down and around the bottom - - minimal cloudiness that will settle in the next few hours.
if fish out - - drain down the tank, pour the sand in. lay a plate ONTOP of the sand - - pour water onto the plate to disperse the water flow - - - this method kicks up less sand than just dumping water on top of the sand and will give you less cloudiness. wait before turning the filter on until most of it is settled or you risk sucking up sand into your filter and jamming it.
i prefer fish out so you can mess around, rearrange etc with out stressing out the fish during the whole process.