Where you cut off the water will depend on the type of water supply you are dealing with - a cold water supply or a hot one, and whereabouts your taps are being fed from. Below are some easy steps to follow for four different situations.
If your tap is connected to the mains, it is relatively simple to cut off the supply. Turn off the indoor stop valve. If it is stiff, it is advisable to use a spanner, or to apply a little oil if necessary. When this has been done, simply drain the remaining water away by turning on the taps until the flow of water has stopped.
If your hot or cold tap feeds off of pipes from the cistern, there should be either a gate valve or mini stopcock available to turn off. The stop valve can be found alongside the cold water tank. When these have been turned off, switch on the tap until the water flow has stopped.
N.B. If you find that neither the gate valve or the stopcock are present, then the cistern itself will have to be drained.
To drain the cistern you must first prevent water entering the system by switching it off at the mains. Alternatively you can tie up the ball-valve by placing a piece of wood across the tank and tying the arm of the ball-valve to it. Either way, the flow of water will be stopped. The bathroom taps can then be turned on to drain out the remaining water.
If for some reason you wish to turn of the outdoor stopcock, you will first need to find it outside of your property. If you cannot locate it, get in touch with your water company. Take of the cover off, and insert the stopcock key. When you have reached the handle at the bottom, turn it clockwise to cut off the flow.