Carry things too far because of celebration (6)
I believe the answer is:
overdo
'carry things too far' is the definition.
(I've seen this in another clue)
'because of celebration' is the wordplay.
'because of' becomes 'over' (eg 'he's upset over it').
'celebration' becomes 'do' (I've seen this in other clues).
'over'+'do'='OVERDO'
(Other definitions for overdo that I've seen before include "Maybe burn" , "Perform excessively" , "Exhaust" , "Be excessive, perhaps in cooking food" , "Use to excess" .)