thanks for your reply Matthew,
Unfortunately I didn't notice when I dismantled the old light casement so not 100% sure if all wires were connected up previously.
The green/yellow was connected to the casement (as metal/brass) but actually the new one I will now fit is just plastic therefore...
i'm new to this but keen to have a go.
Current light switch was damaged when moving furniture.
Bought new switch but not quite the same as the old. I have four wires, red, blue yellow and green. The new light switch that I bought has three slots for wires and another for the earth.
It...