Honestly, the best solution is to fail, in my opinion. I was taught at an early age that academic performance determines the worth of your soul and that if you don't get the most prestigious certification possible, then you're less than human. In addition to that, I didn't have the best possible childhood. As a result, I ended up basing my sense of self-worth on my grades.
Later, I became disillusioned with the idea of education, so I let my performance drop. And I remember the first time I got a B I felt like a second-class citizen. But that's all that happened. I wasn't forced into poverty, the world didn't collapse because of my grade. In fact, people outside of my family didn't even care. So, as I got more imperfect grades, I became more at ease with the idea of being second.
I don't think you should try to stop being a perfectionist. That part is never going away. You just have to moderate it. Ask yourself, 'Is this mistake truly fatal?' If not, try to experience it in a controlled environment, e.g. play chess on a timer and always choose the first move that comes to mind. Then turn off the computer and notice how little it affects the rest of your life. Do this every once in a while, and you'll eventually reduce the pressure to a strong desire.
Later, I became disillusioned with the idea of education, so I let my performance drop. And I remember the first time I got a B I felt like a second-class citizen. But that's all that happened. I wasn't forced into poverty, the world didn't collapse because of my grade. In fact, people outside of my family didn't even care. So, as I got more imperfect grades, I became more at ease with the idea of being second.
I don't think you should try to stop being a perfectionist. That part is never going away. You just have to moderate it. Ask yourself, 'Is this mistake truly fatal?' If not, try to experience it in a controlled environment, e.g. play chess on a timer and always choose the first move that comes to mind. Then turn off the computer and notice how little it affects the rest of your life. Do this every once in a while, and you'll eventually reduce the pressure to a strong desire.