2 gang smart wall switch installation wiring
Mark the wires

See the brown wires making the bounce from L1 to the other L1 and onward?  Mark all these wires "brown" with brown electrical tape, and note that there are 2 of them (and a jumper, that you won't need).   These will be "L". 

See the brown wire going to one of the L2s?  Mark that with gray electrical tape.  That will be future L1. 

See the brown wire going to the other L2?  Mark that with red electrical tape.  That will be the future L2.  

For N, you need to add an additional wire to the bundle of blue.  

For PE, ditto ditto bare/green-yellow.  Oh, wait, there is no PE, WTH??

Make sure this isn't cheap, unsafe, illegal junk

See where it says "CE"?  See where it says "Made in China"?  These things contradict each other.  The tiebreaker is: 


If you bought this retail, at a competent shop such as Wickes, inside the EU, then you are in the clear.  Their retail-gear procurement procedure assures that the CE is backed by an actual, bricks-and-mortar manufacturer inside the EU, who has actually done the testing and certification which the CE represents. 
If you bought this thing at a dodgy shop, flea market, CraigsList, DealExtreme, Banggood, AliExpress, eBay, Amazon Marketplace or any other sort of mail order place (other than wickes.com obviously), then this thing is dangerous junk. Back it goes! This is due to a loophole for mail-order goods, where items are shipped either direct from China or via a dropshipper like Amazon Fulfillment Centers (where Prime comes from).  In those cases, you are the importer and you are on the hook for CE compliance.  


"oooh, I'm so afraid of the CE inspector. Where's this cat gonna come from?" Right on the heels of the fire investigator, and hand in arm with your insurer and mortgage lender. 

By the way, you read right. Amazon is pure junk.  The problem is Amazon blends their listings, showing both Amazon's own stuff and all the third party flea-market sellers on the same listings.  It's very difficult to tell the difference.  And the latest trick of these bastards is to charge nearly full retail as if it were a legit product.  Hunt down the device on alibaba.com, that is the wholesale junk shop that is the ultimate source for most of it; how little they pay there will blow your mind.  I found a $55 pop-up receptacle whose Alibaba cost was $6.