Cheers up, having drunk lager for free (2,5)
I believe the answer is:
at large
'free' is the definition.
(at large means free or released)
'cheers up having drunk lager' is the wordplay.
'cheers' becomes 'ta' (both can mean thank you).
'up' says the letters should be written in reverse (in down clue: letters go upwards).
'having drunk' is an anagram indicator (a drunken version of the letters).
'ta' backwards is 'at'.
'lager' with letters rearranged gives 'large'.
'at'+'large'='AT-LARGE'
'for' acts as a link.
(Other definitions for at large that I've seen before include "Free, maybe escaped" , "Free, not in custody" , "Not yet captured" , "At liberty, escaped" , "awaiting capture" .)