Answer: revising

AnswerCrossword Clue
REVISINGAltering a manuscript
revisingReread work done previously to improve one's knowledge of a subject, typically to prepare for an examination
revisingReexamine and make alterations to (written or printed matter)
revisingAlter so as to make more efficient or realistic
revisingREVISE, to make a new or improved version of
revisingReconsider and alter (something) in the light of further evidence