I am teaching ESL students. How can I improve my teaching skills?
Since no one here knows what your current teaching skills are, it's hard to say how to improve them.
However, here are some websites with some ideas for successful teaching methods:
http://www.google.com/search?q=how+to+teach+esl+students&oq=how+to+teach+esl+&aqs=chrome.1.69i57j0l3.12129j0&sourceid=chrome&ie=UTF-8