I have flown for about 10 years, but my skills are pretty average. I taught my 10-year-old son this summer, and, I have to say, it was great experience that really improved my flying skills.  He made his first solo flight after a few months and now flies a .40 Pulse.    Here's what helped me to teach someone who was a total novice and still pretty young to fly a nitro plane.

1.  Use the "I got it" phrase each time control of the plane is handed over.

2. Instill the idea that practice makes perfect, and so it takes time to learn.

3. Have a routine that you follow.
          a. Prepare and check the plane exactly the same way every time.  
          b. Practice similar skills each time (level flight, left and right turns, approaches, landings/take-offs).