Pick up little devil and travel (7)
I believe the answer is:
improve
'pick up' is the definition.
(I've seen this before)
'little devil and travel' is the wordplay.
'little devil' becomes 'imp' (an imp is a little demon).
'and' says to put letters next to each other.
'travel' becomes 'rove' (roving is a kind of travelling).
'imp'+'rove'='IMPROVE'
(Other definitions for improve that I've seen before include "Ameliorate" , "Make better in quality" , "Train" , "Get or make better" , "Polish" .)