New Smart Switch Wiring

[philwdavies]

I have a new 2-way smart switch to fit but need some advice over the wiring if anyone can help. The old switch has three inputs: Common, L1 and L2. The new one has P, L and a symbol as shown in the photo. Which wire goes where? Thanks in advance.

 

[RandomGrinch]

From the manual:

This smart switch isn't a direct swap for your existing two way switch.
To operate the switch as it is designed - the other switch on the circuit will need to be changed to a push/retractive switch and the wiring repurposed.

Manual attached...

 

[philwdavies]

Thank you. Excuse my ignorance but what is a push / retractive switch? The other end I don't actually use so it just needs to stay on to let the new dimmer control the lights - it's there a way to just make it a one way?

 

[RandomGrinch]

Excuse my ignorance but what is a push / retractive switch?

A retractive switch is a switch you press and it springs back (breaking the circuit), after being pressed.

it's there a way to just make it a one way?

Yes, although two way switches can be wired in a number of ways.
Without a multimeter, it may be a little bit experimental.
Can you post a picture of the wiring for the second switch?