Vacuous nightclubbers zip up, entering live music events with cold drinks (3,6)
I believe the answer is:
gin slings
'cold drinks' is the definition.
'gin slings' can be an answer for 'drinks' (gin sling is a kind of drink). I am unsure of the 'cold' bit.
'vacuous nightclubbers zip up entering live music events' is the wordplay.
'vacuous' means to remove the middle letters.
'zip' becomes 'nil' (both can mean zero).
'up' shows that the letters should be reversed in order (in down clue: letters go upwards).
'entering' is an insertion indicator.
'live music events' becomes 'gigs' (I can't justify this - if you can you should give a lot more credence to this answer).
'nightclubbers' with its centre taken out is 'ns'.
'nil' in reverse letter order is 'lin'.
'ns'+'lin'='nslin'
'nslin' put inside 'gigs' is 'GIN SLINGS'.
'with' acts as a link.
Can you help me to learn more?
(Another definition for gin slings that I've seen is " Iced drinks flavoured with lime juice".)