Hats for those who come first? (7)
I believe the answer is:
toppers
'hats' is the definition.
(topper is a kind of hat)
'those who come first?' is the wordplay.
I cannot quite see how this works, but
'first?' could be 'top' (top can mean the best or first) and 'top' is found in the answer.
The remaining letters 'pers' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'for' acts as a link.
Can you help me to learn more?
(Another definition for toppers that I've seen is " High hats".)