It is very easy to use the O”Cat Premium Clumping Cat Litter Step 1: Fill the clean litter tray with approx. O”Cat Premium Clumping Cat Litter up to 7-10 CMS Step 2: Remove solid waste from the litter tray on a daily basis i. e. clumps to maintain freshness Step 3: Completely replace all of the litter in the litter tray at least once per week. Allow your cat and kittens to feel comfortable, it will take approximately 1 week. Be sure that your cat adjusts completely with it.