When training your kitty to use the litter box it is important to do everything right on your end first. A litter box should always be kept clean, filled enough to cover the bottom, should be easily accessible and away from a busy area. When cleaning the litter box you shouldn’t use harsh chemicals such as bleach and disinfectants. These can be harmful to your cat, so use soap and water instead.
Once you get your kitten inside your house for the first time make sure to introduce them to where their litter box is. Place them inside it and see if they know how to use. Sometimes kittens instinctually know how to use a litter box, or have already learned from their mothers.
If your kitten still refuses to use the litter box, there may be something preventing them. Deodorants may deter them, or obstructive elements of the litter box like a roof if it is enclosed. Removing the cover, avoiding using unnatural scents, cleaning it daily, and changing the litter material are steps you can take to help your kitten get accustomed better.
In the case that your kitten still refuses to use the litter box you may want to visit a veterinarian for more personalized advice. Occasionally, health issues like urinary infections prevent cats from using the litter box. Most importantly, do not punish your cat if they don’t use the litter box. This may cause them stress and further exasperate the issue. Once you do get them to use the litter box reinforce their behaviour with praise and maybe even a treat.