Never say that you know how your teen feels. They'll learn otherwise - without your help. And never imply that their feelings don't matter or will change. Because teens live in the present, it doesn't matter that they'll soon feel differently. State facts instead of opinions when you praise or criticize.
Teens are sensitive about being judged - positively as well as negatively.
Be generous with praise. Praise your child's efforts, not just accomplishments. You're a great artist, is hard to live up to. Set reasonable limits. Teens need them and rules should be consistently applied rooted rules and rooted in your deepest beliefs and values.