Boy managed to get earl to follow orders (4)
I believe the answer is:
obey
'follow orders' is the definition.
(I've seen this before)
'boy managed to get earl' is the wordplay.
'managed' indicates anagramming the letters.
'to get' indicates putting letters inside.
'earl' becomes 'e'.
'boy' with letters rearranged gives 'oby'.
'oby' placed around 'e' is 'OBEY'.
'to' acts as a link.
(Other definitions for obey that I've seen before include "Heed" , "Hear" , "Act in accordance with (law)" , "Do as ordered" , "Comply with (instructions)" .)