I'm going to tell you a secret. I don't handle criticism well.
At all. Even a little.
What I do normally is call my mom and bitch about it, or throw a hissy fit, or vent for a while, and then I feel better, but there may be healthier ways to deal. (Not that those don't have their place, because they do. Certainly.
As an adult, a grown woman, and a recovering bitch, I've learned a few things about accepting criticism graciously. Or at least with a minimum of bloodshed.
1. CONSIDER THE SOURCE. Some folks are trolls, or angry and small, downright stupid, or just poor excuses for people. Some people get off on "fixing" things for other people. Some are genuinely trying to help. For whatever the critique, consider where it comes from. Do they know what they're talking about? Have they ever tried to do what you're doing? Are they an ass? Decide for yourself if what they're saying is a load of crap or perhaps useful. If it isn't? Dismiss it and forget it. Be a duck and let it roll off your back.
2. EVALUATE THE CRITICISM. Although the complaint is probably not completely objective, (few things are) there still may be some truth to what they say. After you've done the inner wince, or even given an, "Ouch, that was painful," take what they've said to heart. I have to remember that I'm imperfect (*gasp*) and that the person making the comment might have a point. Then I have to go back, fix what I've done or remember to do it differently next time.
3. REACT SLOWLY. Sometimes it's best to let it rest for a day or two. Mull it over. Very rarely are knee-jerk reactions the right ones. I find that I get a little bit more perspective after my hurt feelings have had time to mend. And giving it some space before I react keeps me from saying, "Oh, yeah? Well, so's your face!" And then doing that really unattractive red-faced weepy thi9ng that I do.
4. REMEMBER WHO YOU ARE. For me, I try to mentally store up good compliments. And, you have to remember that you are responsible for your own self-esteem, and you can't let stray comments tear you down. If you're a Christian, remember this wisdom: I Corinthians 3:23 - "... you belong to Christ; and Christ belongs to God." He loves me the way I am. And he loves you, too. It's important stuff.
5. BE COMPASSIONATE TO THE CRITICIZER. They might be unhappy in their own right. They might have a horrible life. They might be a pain in the ass. Forgive them, especially if the critique wasn't given in love. Or Like. Or even tolerance. It puts you in a better frame of mind to handle what they have to say.
6. REMEMBER HOW IT FEELS. Choose your own words wisely. Don't be a bitch just because you can. Don't use the fact that you're better at something to tear someone else down. Temper your words. Once they're out there, you can't take them back. There have been so many times that I've had to apologize for a hastily spoken word. Many, many, many times. So put the feeling in the vault, and remember it when you need it.
Now I just have to practice what I preach. Harder said than done. :)