The phrase "making a hash of" means to bungle, botch, or mess up something. On the other hand, there are several antonyms for this phrase, including "nailing it," "executing flawlessly," "doing exceptionally well," "performing expertly," "achieving success," and "mastering with ease." Each of these antonyms indicates that someone has performed a task skillfully, competently, and successfully. These opposites of "making a hash of" suggest that the person in question has worked hard and carefully planned, thus fulfilling the task to the best of their ability. Instead of creating chaos or confusion, these individuals have left a lasting impression of their proficiency and great work ethic.