Step 2 · Turn Off Water Supply
Locate the two water shutoff valves under the sink, one for hot water (typically on the left) and one for cold water (typically on the right). Turn the handles clockwise until they are fully closed. If they are stiff, you may need pliers to get them started, but be gentle. Once closed, go to the top of the sink and turn the old faucet handle to the 'on' position. This will release any remaining water pressure in the lines. A small amount of water will trickle out and then stop, confirming the water supply is off.