To practice good hygiene it is important to remove their stools from the litter tray on a daily basis and to shake the cat litter tray occasionally to mix up the litter.
When the cat uses litter tray the litter most often forms clumps of litter. These clumps should be scooped at least twice a day to remove the soiled litter.
The litter tray should be completely changed regularly (at least once a week) to help to avoid strong odours and to give your cat a fresh area to do their toilet business. Once the old litter has been disposed the litter tray or litter box needs to be washed with warm water and a mild detergent.

Any time you come in contact (use your hands) with the litter tray you must ensure that you wash your hands thoroughly
Click here to see how to Wash Your Hands properly.