Clear a clogged (not stopped) sink or bathtub with a plunger:

1. If you have a dishwasher, pinch off the rubber dishwasher drain hose that leads to the garbage disposer using a clamp or locking pliers. If clearing a bathtub, remove the drain stopper and cover the overflow opening with a wet rag.
   
2. Remove the sink basket or tub stopper and clean any debris from the drain opening.
   
3. Fill the sink or tub with sufficient water to cover the plunger cup, usually about 2 inches. If you are working on a double sink, seal the other sink with a stopper so the plunger can create a vacuum.
   
4. Set the plunger on the drain opening and repeatedly pump it up and down, then pull away sharply to dislodge debris. Repeat if necessary.
   
5. Turn on warm or hot water to flush loosened debris from the drain.
   
6. If the clog remains, use an auger (see below) or an expansion nozzle to clear the drain.
   

Clear a clog using an auger:

1. Remove the stopper or strainer. If unable to do so, disassemble the drain trap and feed the auger directly through the pipe. Make sure you have a pail and rags nearby in case of a water spill.
   
2. Release the setscrew on the auger and begin feeding the cable into the open drain.
   
3. Once the auger tip hits the clog, set the screw and crank the auger clockwise to break up the clog.
   
4. Continue breaking up the clog and moving it down the drain line with the auger. Once there is no more resistance to forward motion of the auger, stop and carefully remove the auger.
   
5. If the clog can't be moved, continue twisting the auger to possibly snag and retract the clog.
   
6. Once the clog is cleared, flush the drain with boiling water.