When choosing a litter for your cat, it is important to consider your cat's preferences, your own preferences, and any health concerns. Clumping litter is the most popular type of litter, but there are also non-clumping, natural, and biodegradable options available. As for cleaning the litter box, it is recommended to scoop the litter box at least once a day, and to completely change the litter every 1-2 weeks.