Depressingly little put into do-it-yourself (8)
I believe the answer is:
dismally
'depressingly' is the definition.
'little put into do-it-yourself' is the wordplay.
'little' becomes 'small' (synonyms).
'put into' is an insertion indicator.
'do-it-yourself' becomes 'diy' (abbreviation for do-it-yourself).
'small' going into 'diy' is 'DISMALLY'.
(Other definitions for dismally that I've seen before include "In gloomy way" , "How one may fail" , "lacking in cheer" , "not very well" , "Badly" .)