I am trying to fit a porch light?

You said it yourself - there's no neutral in the switch and unfortunately you can't magic one up out of nowhere, you'll have to take one either from the nearest ceiling rose or directly from the consumer unit.

Adam
January 2009

You should get an electrician as you clearly do not understand light circuits or how a switch works.
Why do I say this!
Because some clown, who clearly didn't know how dangerous his installation of my outside lantern was forced me to change it. It is now connected to correct sized cable and EARTHED.

Sorry it's not the reply you're looking for but for your safety. Opening up a j/b and deciphering what terminals you need to connect to can be both daunting and dangerous.

Nobby
December 2008