wiring a double switch for two different lights

[mrjay15]

i was wondering if anybody could help me im trying to change a single light switch into a double and run another light from the new second part ov the switch all the wiring is done just cant seem to get the new light to work from the switch im using the new 3 core and earth but the house has the old black red and earth please please help me i dont have much hair left as im pulling it out
many thanks

 

[dingbat]

Go to the top of the Electrics UK forum (this one) and go through the 'For Reference' post. It may help explain to you why your project isn't working.

1. There is probably no neutral at your existing switch, so that's a show stopper for a start
2. I have no idea why you think you need to use 3-core & earth, or are you actually trying to do something different from what you said?
3. Why would you imagine you could do this job when you clearly don't understand how a lighting circuit works? (This is not meant as an insult, just genuine bemusement.)