The dreaded 3 Red Light Switch Wires

[Swimming]

Hello
1 Gang way light switch..

Due to old school wiring, all 3 light switch wires are red, and there is an earth wire Im able to recognise the earth because its yellow and green.

I want to attach a metal front instead of plastic.. How do I recognise the 3 red wires, ie live etc..
I know i have to add an extra earth wire to connect but Im stumped with thw 3 red wires.

I took a photo, one of red wires was in L2 and two red wires in L1

Ive attached photo of the old wiring and an image of the new metal cover..

Wld you point me in the right direction.. thanks a lot

 

[JohnD]

Both switches have three terminals, arranged in a triangle

Of which only two were used on the old switch

So wire the same two wires into one terminal, and the lone one into the other end

 

[terryplumb]

The 2 wires that are together,go together in COMMON
terminal.
The single red into " 1 way" terminal.
The earth conductor/s connect to the earth terminal ,with a fly lead .

 

[Swimming]

Brilliant thank you all so much. I will try again tomorrow. Have a good evening