You should be aware that when you are replacing an existing plug (perhaps because it has been damaged) the colours of the wires in a mains lead may not correspond with the coloured markings identifying the terminals in the plug. Assuming that you have a modern cable with Brown, Blue and Green and Yellow cores you should proceed as follows: The wire which is coloured GREEN-AND-YELLOW must be connected to the terminal in the plug which is marked by the letter E or by the safety earth symbol or coloured GREEN or GREEN and YELLOW. The wire which is coloured BLUE must be connected to the terminal in the plug which is marked with the letter N or coloured BLACK. The wire which is coloured BROWN must be connected to the terminal in the plug which is marked with the letter L or coloured RED.

Electricity can KILL!! If you are in any doubt at all about what you are doing, or your ability to do the work, you should refer any mains connection work to a qualified electrician.