Star will need collection at the end of the day (6)
I believe the answer is:
sunset
'the end of the day' is the definition.
(I've seen this before)
'star will need collection' is the wordplay.
'star' becomes 'sun' (the Sun is a star).
'will need' means one lot of letters go next to another.
'collection' becomes 'set' (set is a kind of collection).
'sun'+'set'='SUNSET'
'at' acts as a link.
(Other definitions for sunset that I've seen before include "Dusk" , "Close of day" , "Twilight time" , "brilliant decline?" , "Period of decline" .)