This decorative item cheers? Not so much, on reflection (6)
I believe the answer is:
tassel
'this decorative item' is the definition.
'cheers? not so much on reflection' is the wordplay.
'cheers?' becomes 'ta' (I've seen this in other clues).
'not so much' becomes 'less' (I've seen this in other clues).
'on reflection' says the letters should be written in reverse.
'less' backwards is 'ssel'.
'ta'+'ssel'='TASSEL'
(Other definitions for tassel that I've seen before include "Hanger-on perhaps" , "Decorative tuft of threads" , "Bunch of cords as adornment" , "Part of a flower" , "Decoration made from a tuft of threads" .)