From: 10,001 Time Saving Ideas
Stop the drips
When a tap drips, turning it off even tighter only makes the problem worse – it probably needs a new washer put in.
Shut the water off at the mains. If you live in a house, the water meter will probably be near your front boundary. If you live in a unit, apartment or townhouse complex, the mains tap may be inside. Turn on a tap to check that the water has stopped running. If the water hasn’t stopped running, call a plumber.
Once the mains water has been shut off, undo the main nut on the leaking tap using a shifter.
There are three washers to replace. These are: the large-body washer (usually red or orange), the O-ring on the spindle (use a pair of needle-nose pliers to remove it), and the tap washer, which should simply drop out of the spindle.
Lubricate the spindle with vaseline, then reassemble the unit.
Once the tap is reassembled, partially open it and turn the mains back on. If your tap is still leaking it means the seat is probably pitted and it will have to be reground. (Seat-grinding kits are available from most hardware shops, or pay a plumber to do it for you.)