To train kitty, start with a small, uncovered box in a quiet location close to where he sleeps. (pets.webmd.com)
It's better to use uncovered boxes when training kittens because it is easier for them to get into and out of the litter box. (bestfriends.org)
Although it depends on the kitty, most cats seem to prefer uncovered boxes, which allow them to move freely and keep an eye on what's happening around them. (pets.webmd.com)