I managed it. And yes I will get the voltage indicator - or can I use my little screwdriver with a light in it?
Thank you anyway for all your help.
Denis
The yellow is connected to the L1 terminal - not the squiggly one. The squiggle one had the reds going in and out.So, in that picture the very top terminal of the three shown is L1.
Am very confused about the wiring. Blue and black connected together - and what is the yellow - not earth I think.....
Not sure how to connect an ordinary double switch. Can anyone help please?