Put aside your anger and actually be nice to someone, no matter how horrible you feel you have become. You can become "one of the nicest people" you'll ever meet, but bear in mind that you are the only one who can make this significant change. Here are some steps to put an end to your horribleness.

 Steps:

1. Find the root of your anger and defensiveness. Are you mean to people because you like them, you're jealous of them, or you can't seem to find their good points? Do you feel as if you're "getting back at the world" for having treated you badly? In reality, it doesn't work that way--you get back what you put out and meanness will rebound on you. Instead, learn to let go of anger and resentment; seek professional counseling if you can't do this by yourself.
2. Turn any insult, mean comment, or unkind statement that you are about to say into a compliment. While trying to turn over a new leaf, you will find the mean voice continues to pop into your head. Instead of letting it speak for you, however, balance it with your thinking voice that can translate the mean words into compliments or kind statements. For instance:
   • "You are so annoying" turns into "You are so confident in yourself all the time, it's great."
   • "That's an ugly shirt" turns into "That's a really interesting pattern on your shirt."
   • "You're so loud and bossy" turns into "You always know what you want out of life, I wish I had that strength of purpose."
   • "You are such a know-it-all" turns into "You're always concerned about me putting my foot in it but you must let me make my own mistakes sometimes."
   • Instead of turning away, give a hug.
3. Adjust your negative criticism. Try using the sandwich-style-style critique instead of being blatantly negative about someone's actions or words. Start with a compliment about the person, then say something "constructive" about what has gone wrong or bothers you, then end with another compliment. Other ways to adjust your preference to say things negatively include thinking through how this comes across to others:
   • Ask yourself: "If I say this, will it really have a positive effect, or could it have a negative one?. Will I hurt this person, If I say this, or act this way?"
   • Check yourself. When you are talking to people, think "Am I saying this in the nicest way I can?"
   • Is it how you would like someone saying something to you?
   • Know the difference between assuming that you know better; even where you do, nobody wants their nose rubbed in superiority.
4. Keep other people's feelings in mind, all the time. It's an old but true phrase: If you can't say anything nice, then don't say anything at all.
   • Put yourself in other people's shoes. How would you feel if other people treated you the same way?
5. Don't judge people before you discover what they're really all about. First impressions can often be misleading, and couched in your own biases. Get to know people before you decide you don't like them.
   • Remember that people are different. What might be funny to you might be offensive to someone else.
   • Give everyone the benefit of the doubt. Let them have a second or even third chance.
6. Realize that the world doesn't revolve around you, and you aren't the only one with strong feelings or problems.
   • Consider the reason why you don't like someone. Could it be possible that they are a lot like you, and the things you don't like are the things you do too?
7. Take mental notes from people you know who are nice. Notice the differences between what you both say and do to other people. Put into practice some of the things you have learned and see how differently people respond to you.
8. Lend a hand or a shoulder to someone who isn't at the top of your favorites list. Make that effort and see what you get back - maybe nothing, or just maybe you'll discover your best friend.
   • Offer to help. If you see someone struggling or doing anything, offer to help, even doing something as simple as carrying a bag of groceries. Offering help will take you out of your comfort zone initially but you'll end up feeling good about yourself when your help is accepted.
9. Use a reminder prop to pull back your attitude. Wear an elastic band around your wrist. When you feel you are about to say something mean, give the band a snap to discourage yourself.
10. If you are still having trouble accomplishing this task, surround yourself with others who can help you. While the process can be challenging, seek support from friends and family who can guide you to slowly alter your personality. The best way to ultimately change this habit is to be held accountable for your actions by people you trust.