Do a bit more somewhere in London (5)
I believe the answer is:
acton
'somewhere in london' is the definition.
(I've seen this before)
'do a bit more' is the wordplay.
'do' becomes 'act' (I've seen this in another clue).
'a bit more' becomes 'on' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'act'+'on'='ACTON'
Can you help me to learn more?
(Other definitions for acton that I've seen before include "English statesman" , "Gladstone's adviser" , "Part of the London borough of Ealing - British historian, d. 1902" , "Respond in accordance with - London district" , "London area" .)