Position the sink’s pedestal on the floor, lining the connections on the pedestal up with the plumbing connections in the wall. Place the sink’s bowl on the pedestal and place a level on the bowl.
Shift the sink’s bowl from side to side and front to back until it sits level. Mark on the wall the location of the mounting holes in the sink bowl and mark on the floor the mounting holes for the pedestal, and then remove the bowl and pedestal.
Drill guide holes where you marked the sink’s mounting holes. Replace the pedestal and sink bowl, lining up the mounting holes in the bowl and pedestal with the guide holes you drilled. Drive lag screws through the mounting holes in the sink’s bowl.
Measure the distance between the bottom of the sink and the floor. Cut 2 by 4 boards to the same distance and place them between the floor and the bottom of the bowl on either side of the pedestal, and then remove the pedestal.
Thread the water supply lines onto the faucet connections on the bottom of the sink’s bowl and the water supply valves on the wall, tightening the connections with a pair of adjustable pliers. Thread the tailpiece pipe into the sink’s drain piece, thread the trap piece onto the tailpiece and thread the pipe elbow onto the pipe in the wall and the other end of the trap. Tighten the pipe connections as much as possible by hand.
Turn on the sink’s faucet and run water down the pipes for two minutes or more. If the pipes leak, remove them and wrap pipe tape around the threads, and replace the pipes and tighten the connections again. Slide the pedestal back under the bowl, lining the holes in the floor up with the holes in the pedestal. Drive the mounting bolts included with the sink into the holes in the floor using a socket wrench.