As an art instructor, you never want to be stagnant. Much like your students, you want to continue to evolve. Here are a couple of ways to improve your teaching skills:
Take a class
When is the last time you sat in the student's desk instead of teaching up front? If it's been a while, you may want to change things up. Switch the roles by signing up for a class so you're the one doing the learning. Pay attention to the instructor to see what teaching methods you find helpful. Sometimes the easiest way to improve as a teacher is to become a student yourself. This experience can help your improve your own instructing styles.
Allow for feedback
As a teacher, you can gain a lot from feedback. Consider putting a comment box in your classroom. There, students can anonymously share useful ideas, questions, feedback and advice. It also allows for an open classroom environment - which will benefit you and your students alike.
"You have an abundance of resources at your disposal."
In this modern age, there are plenty of inexpensive and accessible resources to help you improve your teaching skills. Head to your local bookstore, and peruse the teaching aisle. There are plenty of guidebooks that cover a plethora of subjects. Online forums can also be helpful in getting advice from experts or other teachers. In addition, there are lots of seminars for instructors who are looking to brush up on their teaching style, in person or online. Be sure to do some research on what is available in your area - you may be surprised at how much you find!
Meet with other teachers
Talking to people in similar job professions has a multitude of benefits. You can swap stories and lesson plans, or learn from each other's mistakes and successes. Speaking with someone who empathizes with your job allows for deeper, more significant conversations that can impart more knowledge about your job and yourself. Connect with art teachers at your school or community, no matter what medium of art they practice (even if it's not art at all). There are few who will understand your situation better, and the advice you receive will actually come from a place of experience and expertise. After all, no one knows better than a teacher.