Cats have a natural instinct to eliminate in sand or soil, and kittens also learn from observing their mother. Kittens usually start learning to use the litter box at 3 or 4 weeks of age, so by the time you bring your kitten home, she will likely be used to using a litter box.
You will not need to train your kitten to use the litter box in the same way that you would housebreak a puppy. However, it is important to make sure your kitten knows the location of the litter box in her new surroundings. Make sure the box is not in a noisy or hard-to-reach place. Soon after you bring your kitten home, take her to the litter box at a quiet time. Place her into the litter box, gently take her front paws and show her how to scratch at the litter once or twice. Don't worry if she jumps right out again. Place her in the box at the times throughout the day when a cat would normally go to the bathroom: first thing in the morning, and after meals, playing, and waking up from a nap. Remember that cats prefer privacy when using the litter box, so once you see that she has used the box, leave her alone.
Most cats will make the adjustment to a new litter box without any problems. However, if there are any accidents, don't scold or punish your cat. Yelling or using a squirt bottle will only confuse and scare your cat, and she won't understand why you are upset. Instead, clean up the accident with an enzyme cleaner to remove stains and odor. Then go back to square one, placing the kitten in the litter box frequently until she starts using it. If the accidents continue, or if you are noticing any diarrhea or straining, have your kitten examined by your veterinarian to rule out any possible medical problems. Cats with urinary tract disease or intestinal parasites may stop using the litter box.