Come clean. “The truth hurts, but not as much as being caught in a lie.” If you’ve screwed up, don’t try covering your tracks. You will only dig a deeper hole.
Take full responsibility. If you missed a deadline or acted like a jerk, “admit it, acknowledge it, and recognize the problem.” Tell the whole truth immediately, rather than try to hide the worst aspects; “a piece of the puzzle might be discovered later on, which can lead to tremendous mistrust.”
Know your audience. A quick apology might work with your wife, but your children, your boss, or your co-workers may want more detailed contrition.
Say it in person. “Unless you’re fighting with someone overseas,” apologizing via e-mail is “never wise.” Not only is it “impersonal and cold”—you also won’t even be able to tell if your apology was accepted.
Source: Best Life