Cleaned a clumsy fellow on couch (7)
I believe the answer is:
swabbed
'cleaned' is the definition.
(swabbing is a kind of cleaning)
'a clumsy fellow on couch' is the wordplay.
'a clumsy fellow' becomes 'swab' (I can't explain this - if you can you should believe this answer much more).
'on' says to put letters next to each other (in a down clue, letters appear on others).
'couch' becomes 'bed' (I've seen this before).
'swab'+'bed'='SWABBED'
Can you help me to learn more?
(Another definition for swabbed that I've seen is " Mopped".)