The phrase "cleans up one's act" usually means to improve one's behavior or become more responsible. Its antonyms are usually negative attributes, such as being reckless, irresponsible, or careless. Alternatively, one could use words like disregard, neglect, or abandon to show a lack of responsibility, particularly in one's personal or professional life. You could also use words like degenerate, corrupt, or degenerate to describe someone's negative actions or behavior. Overall, the antonyms of "cleans up one's act" imply a lack of control, a lack of self-discipline or the unwillingness to take responsibility for one's actions.
