The absolute best way to improve is via the criticism and suggestions of your peers and those further along the path to mastery than you are. Based on my observations however, there are a number of misconceptions and misunderstandings about both the purpose and process to go about giving a crit.
First - Do not give an unasked for public crit.
Let me say that again: DO NOT GIVE AN UNASKED FOR PUBLIC CRIT.
Once it's on someone's website, or tumblr, or whatever, let it lie. Don't offer suggestions in comments, don't be a dick and tear it apart. If someone has publicly asked for comments....maybe...and even then, I'd private message those comments. Artists rely on social media for contacts, for jobs and for new clients. Pointing out flaws that perhaps clients can't see is a dick move.
Ok, now that that's out of the way, let's talk about the crit itself. When I was in art school, I swear to god I sat through crits that came straight out of "Art School Confidential." It was a lot of ego stroking, and if someone dared make a negative comment, they were attacked by everyone for being mean. The point of a crit is to help an artist improve, not to make them feel good about the work they've just made. If you want to be complimented, show your painting to your mom - I'm here to help you get better.
The best crit I've ever gotten, and the model I've used since, was given to me by Eric Velhagen at IlluxCon several years ago. All he did was ask me questions, to lead me to improving the piece. I realized that I already knew the answers to most things, and it helped train me to crit my own work, which is key to being a professional. Some ideas for questions:
- How do you feel about the piece? This will help set the tone of the crit
- What are you trying to say with it?
- Who is your target audience?
- What is the primary subject of the image?
- What is your character doing?
- Do you feel like the anatomy and rendering works for what you were trying to say?
Based on those questions, you can drill in. Eric looked at my piece and asked, "What are those things in the background?" I responded with "Oh, those are mountains." He then asked me, "Is there a reason they are lighter in value than the sky?"...and then I died inside, because of course, there was no reason at all. Let me tell you though, I internalized the HELL out of that question, and it has improved my landscape design - I've never made that mistake again.
What a crit is NOT - It is not your chance to get on your soapbox. It's not a time to attack the artist for his subject matter, or their political stance, or anything like that. If they wanted to make a porn-y pinup of a My Little Pony character, and they succeeded at that, don't attack their idea in the crit. You won't like every piece of work. You won't like the subject, the audience or the execution - that doesn't make it bad. I've heard people rail against comic artists for drawing over-sexualized women, and that is a valid complaint - but a crit of the work is no time to bring that up. It's not helpful to the artist to tell them they shouldn't be drawing or painting what they wanted to. You have to, to some extent, leave your ego and your personal opinions at the door.
As I said, I prefer to just ask questions, but if you do make an observation of something that is wrong in an image, it is your duty to also offer some suggestions for fixing it. Don't just say, "You anatomy is bad", without saying, "You need to focus on the muscles of the arms, and really pay attention to the flex of the biceps." If the perspective is bad, point out where, and offer suggestions as to what the objects should be doing in space.
Also remember that chances are, the artist won't fix *this* painting. Look for observations that will be helpful for the next one. Try to generalize when possible. Whatever you do, don't say shit like, "I wonder what this would have looked like if you did it as a watercolor instead of digitally." I had a classmate offer that particular gem in school, and I wanted to push her out a window. That's not helpful, it is just an attack on a medium. You could say, "Based on your line style and color choices, maybe you should try watercolor instead of digital - it might help you achieve the look you seem to be going for." See the difference?
Crits should be like improv theatre - Every suggestion should offer a path to a future dialog, and to change. Leave room for the artist to respond, and leave room in yourself to learn what they were trying to say.
Thanks for reading, and I hope you found this helpful - It works in formal school settings, it works when you're drawing with your buddies at Starbucks....not only will learning to do this help others, but I think you'll find it sharpens your own sense of what to do with a painting.