Inside your head there is a voice. Where it came from isn't all that important, but it'll probably take on the voice of one of your greatest critics. Maybe your parents, maybe a teacher, someone perhaps who you thought was your friend but really isn't.
"You're doing it wrong."
"That totally didn't work."
Sound familiar? This butthole voice is what Seth Godin calls "The Heckler." While I think you should all go read Seth Godin's description here about The Heckler, we'll sum it for you in a sentence: "The Heckler is part of your primal, lizard brain that you can't ever really get rid of. If you fight, it will fight harder, and the only way to get rid of it is to disable it."
So, Monkey and Seal, how do you disable the Heckler? The Heckler is a big bully that takes pleasure in your resistance - it enjoys the fight, and is just waiting for you to tell it to shut up so you can yell louder. Using one simple phrase will take the wind out of the bastard's sails, making it weaker and quieter. That phrase is:
If you've ever been taunted, or teased, or a victim of bullying, the immediate, primal urge is to react against the insults. You refute the disparaging claim or you try and throw it back at the bully. However, as it is the nature of a bully, it will take pleasure in your obvious reaction and will continue on its bully ways of attacking you. However, it stops being fun for the bully when you don't react, or care.
Instead of "No, my painting doesn't suck, yours sucks!" it's "My painting sucks? So what?" Its the exact opposite reaction the Heckler needs to continue on the fight.
"That brushstroke doesn't work. So what?"
"I messed up in that last routine. So what?"
"I didn't win that competition. So what?"
Now we don't want you to turn into some self-effacing downer that's just all negative. By saying "So what?" the goal is not to get down about whatever deficiency (imaginary or real) that your inner Heckler is bringing up. The goal is to realize that whether the Heckler is right or wrong, it's not the end of the world.
The skies won't rain blood just because you missed a note in that last solo. The earth won't implode because you didn't render those hands enough. The sun won't die just because your proportions are off.
If we have the fortitude and imagination to dream, we also have the imagination to whip up illusions of grandeur where we become painfully inadequate compared to Everyone Else. However, even when we are at the height of our careers and a huge mistake could cost us everything, we still tend to overreact to mistakes and to exaggerate what Everyone Else thinks about us.
If you're an aircraft controller, the stakes are high. Planes could crash, people could die. If you're a painter, most likely you are not going to be put in a situation where your performance is a life or death situation. The Heckler is telling you that it's the end of the world, that your imperfection (perfection is overrated anyway, remember?) is a huge deal. It's not. You screwed up. So what? Learn from it and grow. There are no mistakes, just opportunities for growth.
The point of disabling the Heckler is not to stop criticism. The point of disabling the Heckler is taking the work-stopping, genius-interrupting, creativity-killing emotional sucker punch that comes with the taunts of the Heckler and taking the poison out of them. Criticism is good, it helps you grow, but if you take it personally and shut down, then all it's doing is getting in your way of living up to your true potential of making something magical and wonderful.