Step 6 · Connect Water Supply and Sprayer Lines
From under the sink, attach the hot and cold water supply lines to the corresponding faucet tailpieces (hot on the left, cold on the right). Hand-tighten the coupling nuts, then use your basin wrench or adjustable wrench to give them an additional quarter to half turn. Do not over-tighten. Connect the other end of the supply lines to the shutoff valves if you are replacing them. Connect the side sprayer hose to its designated port on the faucet body, often a quick-connect fitting.