im going to say this and hope i dont get shot down in flames, for it, it sounds like your not an electrician, and therefore, my advice to you would be, if you arnt a trained spark, and are having to ask something quite basic, like this then you dont appear to have the knowledge to be able to carry out this work, my advice is get 3 quotes from local sparks and employ a qualified sparky to do this work, this is because they can use the testing procedures to make sure the new wiring and the existing wiring is installed safely and is earthed as it should be etc,