A broken or damaged faucet can cause quite some damage to the house, as well as the piece of mind of the residents. As I have been through such a plumbing travesty in the past, I decided to share my knowledge and findings with you.
Basically, faucets are extremely important in any home. They dispense water, making the regular, day-to-day activities relatively easier. Hence, any damage to the faucet can, indirectly, lead to damage to the house. More so, the residents of the house also face their fair share of worries. Hence, it is very important to maintain your faucets and repair them, when broken, at the earliest.
How to Repair a Faucet
Now, let's start off with repair instructions for that leaky faucet. First step, turn off the water supply. The last thing you want is a gush of water coming right at you when you take out the faucet. Once you have turned off the water supply, you can proceed to taking out the faucet handle by unscrewing the buttons and screws. Next, remove packing nut, being careful not to scar metal. Twist out stem or spindle. This can be done by turning it in the same direction, as you would to turn on the faucet. Now, remove the screw that holds washer. Loosen the screw, if necessary by using penetrating oil. Examine screw and stem, replace if damaged. Fasten the new washer to the stem. Reinstall assembly in faucet. Turn stem clockwise. With stem in place, put packing nut back on. Now, you may reinstall handle. Lastly, check for leaks.
Now, in case the dripping hasn't stopped even by replacing the washer, then the next probable issue may be a faulty valve seat. This problem can be solved by replacing the valve seat. This is relatively easier with a tool called a seat wrench. Simply insert the seat wrench into the seat and turn it counter clockwise. Once the old seat is out, replace it with an exact (non-damaged) duplicate. In case the replaced seat is different, there is a possibility of further leakage and faucet damage. So, make sure that you check the make etc. of your current seat and get the exact one. Once done, check for leaks.
In case, the valve seat is not an issue either, it could be faulty packing or a fault with the O-ring. In either cases, you need replacement. Make sure to turn off the water, before you remove the faucet handle. Next, replace the item that needs to be replaced (the packing or O-ring). Check, once again, for a leak.
If none of these instructions seem to work, it could be because your faucet is of a different type. In either case you will need a professional to come and help you out. Mind you, playing with a leaky faucet is as dangerous as playing with fire. Ok! I am exaggerating again. But, one option that will always work (especially with recurring problems with the faucet) is replacing the entire faucet. This is mostly a better option, as you are not using a faulty item then and you are solving quite a few problems in one go.
So, this is where I sign off. All the best with your faucet.