Turn off the water using the two handles on the supply lines underneath the sink. If the old faucet has already been removed, skip this step.
Slide the plastic gasket onto the bottom of the cover plate. The two inlet hoses extending from the bottom of the cover plate go through the gasket's center hole. Position the other hole on the cover plate's right side.
Spread a layer of plumber's tape around the gasket's bottom edges. Place the two inlet hoses through the hole in the countertop and lower the faucet until it is resting on the countertop's surface.
Reach underneath the Kraus faucet and slide the rubber washer, metal washer and lock nut over the two hoses. Use a screwdriver to tighten the screws on the lock nut, securing everything in place.
Loosen the screw on the end of the adapter. Push the adapter onto the flexible spray hose until it clicks. Slide the weight onto the spray hose and tighten the screw on its side to hold it in place. The weight prevents the hose from becoming tangled as you pull it in and out of the faucet.
Wrap plumber's tape around the threaded pipes on the bottom of the sink. Wrap the tape in a counterclockwise direction. Wrap plumber's tape around the threaded tips of the water supply lines under the sink.
Screw the ends of a short piece of flexible pipe to the supply lines. Use a wrench to tighten them securely. Position a bucket under the sink to catch water. Turn the handle to allow water through the pipes. Do this to one pipe at a time to clean out the system. Turn the water supply off afterward.
Attach the loose ends of the flexible hoses to the two inlet hoses on the bottom of the faucet. Tighten them with a wrench. Attach the flexible hose on the left to the inlet hose on the left and the flexible hose on the right to the inlet hose on the right. Crossing the hoses causes the operation of hot and cold water to be reversed.
Restore water to both supply lines. Turn on the faucet and look for leaks.