Step 8 · Connect New Water Supply Lines
Connect the new (or existing) flexible water supply lines to the hot and cold water inlets on the new faucet. The inlets are usually clearly marked with red for hot and blue for cold. Thread the nuts on by hand to avoid cross-threading. Once hand-tight, use an adjustable wrench to give them an additional quarter- to half-turn. Do not overtighten, as the rubber seals inside the connectors can be damaged. Now, connect the other ends of the supply lines to the corresponding hot and cold shutoff valves on the wall, tightening them in the same manner.