Just simply press the self-cleaning switch for 5 seconds to activate the function (method varies for different water dispensers) and let it do the rest automatically.    Do note that you will need to wait for 30 to 90 minutes before you can dispense water, so you may activate it before bed to let it run overnight. It’s recommended to activate the self-cleaning ozone feature once every 2-4 weeks to maintain the safety and cleanliness of your drinking water.