Right, I bought a new light switch as the one here was actually an old sock in the wall padding the gap to hold a broken but working live switch. The new one looks different to the old one so I do not know which holes to put the wire in. There are just the 2 blue wires going through old switch. The new one has 2 banks of 3 holes each side at back of switch. one bank has screws to hold wires, the other bank of 3 does not have holding screws. On the rear of switch are markings: Screw side: X1, L1, X3. The unscrew holes are marked X4, L2, X2. I do not really want to take the thing to bits in case funny bits fall out. I am good at taking things apart, but not so clever putting them back, (but am finding a new way of beating that system with my dig camera. Photo is first then I have a picture of how to put it back again).Therefore, when you press the switch, I have no way of knowing where the contact breaker is. If there are now screws on one side it would seem that you should only use the 3 holes that do have screws. So it is just a matter of which hole to put one piece of wire and which for the other. Funny to have 3 holes with no screws though. Please don't tell me to get a professional in because I just cannot do that every time something needs doing. Just kindly tell me if it matters which holes I use. Just an old lady but am already installing double sockets in place of single bare wires, so I know I can manage it. If only someone will tell me how. ALSO Light fittings: for the life of me, I do not see how one of their light hooks can serve to balance and hold fancy lampshades on the ceiling. Are you supposed to get chain and attach it all to say 3 points of lampshade. Think I prefer to install uk roses. As to wall lights, there are wires sticking out of 2 holes in the wall. I would not expect the wires to take the weight of wall lamps and shades. Those hooks again? I don't know. Thanks to all in anticipation.xx