Kicking off at hot time of year, United score (12)
I believe the answer is:
inaugurating
'kicking off' is the definition.
('inaugurate' can be a synonym of 'kick off')
'at hot time of year united score' is the wordplay.
I cannot really understand how this works, but
'at' could be 'in' and 'in' is found in the answer.
'hot' could be 'in' (both can mean fashionable) and 'in' is found in the answer.
'time' could be 't' (abbreviation) and 't' is located in the answer.
'united' could be 'u' (abbreviation) and 'u' is present in the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Another definition for inaugurating that I've seen is " Officially opening".)