One reason people love living with cats is because they have a natural instinct to use the litter box. When it comes to litter box training, the process is pretty simple.
When you bring your new cat home, show him where the litter box is. Pick him up and place him in it. He may sniff around and scratch a little, or he may use the box right away. Once he knows where the litter box is, do not move it. If you do, you will confuse him and he could have an accident. If you must move it, show your cat where you have put it. Do not expect him to find it on his own.
When setting up the litter box, choose a quiet location that does not get a lot of household traffic or noise. A good place to keep it is in a spare bedroom or bathroom. Make sure that the door to the room is always open so your cat can use it at all times. Do not place it near his food or water dishes. Cats do not like to soil near where they eat. Instruct family members especially children to leave your cat alone when he is using the litter box.
Clean the litter box every day even if you use clumping litter. One of the most common reasons that cats develop litter box problems is because the box is not clean. Some will stop using it if you change brands or types of litter. To avoid this, try to buy the same litter your cat was using before he moved in with you. If you must change brands or types, gradually mix a blend of the old and new litter until he becomes accustomed to the new brand.
If you have more than one cat, each should have his own litter box. Cats are territorial and do not like to share. Keep the boxes in separate rooms or far enough apart so that each cat has a sense of privacy.