Dexterous after opening of soft drink (6)
I believe the answer is:
shandy
'drink' is the definition.
(shandy is a kind of drink)
'dexterous after opening of soft' is the wordplay.
'dexterous' becomes 'handy' (I've seen this before).
'after' says to put letters next to each other.
'opening of' suggests taking the first letters.
The first letter of 'soft' is 's'.
'handy' after 's' is 'SHANDY'.
(Other definitions for shandy that I've seen before include "mixed drink" , "Drink made of beer and lemonade" , "Beer and lemonade mixture" , "Light beer" , "Beer/lemonade drink" .)