Clarion was my first experience of a writers' workshop. Or writing group. Or really any situation where my writing was critiqued outside of turning in my dissertation chapters to my advisor. As far as learning to take criticism of my work, it was pretty much trial by fire.
Here's how it worked: When it was my story's turn to be critiqued, I would sit, silently, while the seventeen other participants in the workshop each had two minutes (with the option of asking for thirty seconds of extra time) to say what they thought about my story. Then, when that was done, the instructor (or instructors, in the case of the last two weeks) had as much time as he or she desired to say things about my story. When you have that little time to speak, you normally do not begin with, "I loved this." Or if you do, it is quickly followed by, "having said that..." and a two minute list of all the things that were not loved. Only after all of that was finished, could I speak. I don't remember who it was who suggested that the person being critiqued should write down what people were saying rather than trying to remember what was going on. I do know, some days, that's what kept me from breaking down.
I think I only cried once.
But as difficult as some critiques were, once I understood that people were motivated not by a desire for cruelty, but a desire to make the story better, it got easier to sit through them. The thing that became difficult was knowing what to do after, when it came time to revise.
I think one of the most important skills a beginning writer can have is the ability to take criticism. I also think an important corollary to that is that knowing when not to take criticism is equally important.
Sometimes the when not to point is easy to see, because your beta-readers will agree that something is wrong, but split, and in diametrically opposed ways, as to how the wrong can be fixed. But sometimes the fix that is being proposed, that nearly all the well-meaning and helpful people who have read your story agree on, is actually wrong. It will break your story. Learn to recognize that. Learn to trust your story.
But don't ignore the critiques. Even if you know something won't work, or you hate the fix that is being proposed, take the time to think about why the solution is unworkable, why you hate it. You will learn more about your story, and maybe an entirely new solution will appear.