A bit stuck?

sounds like switching was done at switch not at the cieling plate. 2 red wires are I (expect ) live coming in from wherever and live to switch. 1 of the the blues is coming back from switch so is actually a live and other blue is the proper neut.
To add switch for out side light.
1 put red with others this goes to common on switch
2take red-brown, black -blue, earth to light
put blue-black at switch with other blue-black as this shoud be neut
red should then go in toother side of red taken from other reds.
wire light up as red live blue neut and earth.
if you have tester take reds apart and only 1 red-brown should be live, test other red-brown should be at other light fitting. It is then like cieling fitting.
1 in from light
1 onto next light
1 as switch wire- with neut as the return from switch.

eddy mccarthy
July 2008

This is correct.

2 browns, 1 from live feed in and 1 to light switch
2 blues, 1 neutral return and and 1 to light switch (so it's live when the switch is on). This second blue should have some brown tape on it.

Connect 2 browns together, both blues to light - either side (1 to live, 1 to neut) and earth to earth terminal.

Jobs a goodun

Mr handy Andy
April 2008