Instructions: For best results, do not mix with non clumping cat litter. For first time use, start with an empty, clean cat litter box. Fill it with 3 to 4 inches of Fresh Step litter. Remove clumps and solids daily and dispose in trash. Do not flush. Add more Fresh Step clumping cat litter to refresh your litter box. Maintain level of litter at 3 to 4 inches.