Turn off the water control valves located beneath the sink by turning the two valve handles in a clockwise direction. Although it is not necessary to turn the water supply off, you will avoid the risk of inadvertently turning the faucet on by doing so.
Pull the spray head out of the sink, and grasp the handle mount at the tip of the hose. Rotate the sprayer head in a counterclockwise direction while holding the mount stationary until the sprayer head detaches from the mount to expose a large rubber washer.
Lift the large rubber washer off the tip of the sprayer hose, and press a new washer onto the tip of the hose.
Twist the sprayer head onto the handle mount until snug.
Hold the sprayer head stationary, and turn the sprayer head’s aerator in a counterclockwise direction until the aerator detaches from the sprayer head.
Scrub the interior and exterior sides of the aerator with a small brush dipped in vinegar to remove the mineral deposits.
Twist the aerator onto the sprayer head until snug.
Turn the water control valve handles in a counterclockwise direction to turn on the water.