It may be hard to follow (3)
I believe the answer is:
act
'it may be hard to follow' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for act that I've seen before include "Play (a role)" , "Take steps" , "Perform(ance)" , "Assumed attitude" , "Perform - part of a play" .)