An apology note expresses your regret when spoken words just aren't enough. Maybe you've hurt your loved one to the point where she doesn't want to speak to you, or perhaps the one you love lives far away. A heartfelt, handwritten apology note should not only convey your regret, but also should offer a resolution for the injured party. Your note's length is up to you, but any apology letter should focus on your apologies and not on pointing fingers.
Write your note as soon as possible. An apology letter is much more affective and heartfelt when sent within a week of the argument, rather than a year later.
Greet the injured person kindly in the letter. Use a special nickname if you have one.
Be direct. Don't put off stating the purpose of your letter with small talk. Instead, immediately say, "I'm sorry for yelling at you last week on the phone. That was uncalled for."
Keep your tone collected and don't be over dramatic. For example, don't say, "I can never forgive myself for my behavior." Instead say, "I hope you can forgive me for my poor behavior."
Avoid excuses. Take responsibility for your own actions. An apology letter is not the time to state the other person's shortcomings. While you can state the other party's influence on your actions, be brief. For example, you can say "When you said you didn't like my haircut, it really hurt my feelings. I shouldn't have lashed out at you like I did, and I am so sorry for my hurtful words." Don't say, "You were mean to me, so I was mean back." Be cool and collected in your note.
Remind the other person that you still love him or her and sign your name.