Go on run and walk (6)
I believe the answer is:
ramble
'go on' is the definition.
(rambling is a kind of going on)
'run and walk' is the wordplay.
'run' becomes 'r' (cricket abbreviation).
'and' says to put letters next to each other.
'walk' becomes 'amble' (ambling is a kind of walking).
'r'+'amble'='RAMBLE'
(Other definitions for ramble that I've seen before include "Walk in the countryside" , "Walk; be discursive" , "Walk or wander" , "Go as fancy leads" , "Wander where you please" .)