Using Instructions: Step 1: According to the pet's size and nails characteristics, select the suitable port for your pet. Port 1 is for small-sized pets to grind nails; Port 2 is for medium and large pets; Port 3 (side) is for fast grinding. Step 2: Holding a nail grinder with the right hand, open the switch of the nail grinder. Pinch pet's paws with the left hand, put pet's nail gently into the hole, you can begin to grind the pet nails.