Check to make sure your sink can accommodate a sprayer hose. Most sinks have an extra hole to the side of the main faucet. Use the extra hole next to the faucet for a sink sprayer attachment. Some people use the extra hole for a soap dispenser and if it has been you will need to remove it before installing the sprayer. Also, check under the sink to make sure there is a diverter connection on the water supply line that can accept the water supply hose of the sprayer.
Turn the water supply off to the faucet and drain.
Remove the soap dispenser or cover over the auxiliary hole next to the faucet. If there is a soap dispenser installed you will need a basin wrench to loosen the retaining nut on the dispenser.
Place the shroud for the sprayer in the hole and tighten the retaining nut below to keep it in place. Feed the sprayer's hose down through the shroud and place the sprayer in the shroud.
Find the end of the sprayer hose and connect it to the diverter connection on the water supply line. Turn the water back on and test the sprayer. Tighten any points that show a leak.