Step 6 · Connect the P-Trap and Drain
Now connect the drain plumbing. Attach the P-trap to the sink's drain tailpiece. The P-trap kit will include slip nuts and washers. Ensure the washers are oriented correctly (tapered side towards the threads). Align the other end of the trap with the drain pipe in the wall and connect it. You may need to trim the pipe from the wall or the tailpiece from the sink for a perfect fit, which can be done with a hacksaw or tubing cutter. Hand-tighten all the slip nuts first to ensure proper alignment, then give them a final quarter-turn with channel-lock pliers. Do not over-tighten plastic fittings.