A rebbe in cheder once came into class late, and all the children immediately scurried to their places to learn Torah. There was one child who pointed at his watch with immense excitement. The rebbe thought that the child was rebuking him for coming late. The rebbe wanted to reprimand the child for his chutzpah, but he reminded himself of the ideal of pushing off the anger for later, so he decided to leave it alone for now and speak to the child about it during the break. The entire time the rebbe was teaching, that child kept looking at his watch, touching it, playing with it. The rebbe understood that the child was once again hinting to him that he came late, but kept his anger under control. The bell rang, indicating the first break of the day. The child excitedly ran up to the rebbe, pointed at his watch, and said, "Rebbe! Look! My father bought me a new watch!" The rebbe realized that the child wasn't insolent at all. He was sharing his good fortune. If the rebbe had responded impulsively with anger, the child would be devastated. Time enabled him to learn the real story.
And here's another story, that shows the benefit of pushing off anger until later: A young couple got married, and a week after the sheva brachos, the father-in-law asked the son-in-law to lend him fifty shekels. The new son-in-law gave him the money, and he whispered to his wife, "We'll see whether it will ever come back." The father-in-law was insulted. "Why does he suspect I won't pay him back?" As a result, the father-in-law started worrying about his daughter’s happiness. He thought, "My daughter is married to someone who doesn’t think straight." For the next few weeks, the father-in-law didn’t sleep well at night. One day, the father-in-law couldn’t contain himself any longer, and he asked his daughter straight-out, "Why did your husband say, 'we'll see whether the money will come back'? Does he suspect that I'm a crook?" Laughing, the daughter said, "My husband has a game. He writes his name on his bills to see whether they’ll come back to him again." Had the father-in-law angrily reproached his son-in-law immediately, it might have burned bridges and ruined a good relationship –all be because of a misunderstanding. By holding his anger in check, and allowing time to pass, the father-in-law found out what indeed took place.
There are other approaches that tzaddikim used to postpone reacting to anger. One method is to fill up your mouth with water so you can't speak. Another approach is to have a special anger suit that is worn only when you are angry. When you feel you just have to rebuke someone, put on that suit first, and by that time, you will have reconsidered.