Use a little dab of super glue or Thick 5-15 sec CA from the hobby shop. I use this stuff all the time and that's what I used on my Oompa. Just be careful and only get this stuff where you want. Double check the direction of the swirl on your pompons, and make sure they are facing the correct way before gluing. You got one shot at this once you apply the glue. Apply glue and quickly stick on and hold it for 30 sec to be sure and let go.
It's easy, took me 2min. total.
I'm still working on my Wonka, gotta futz the Wonka hair. I also repainted the eyebrows on my Oompa head too. I made them thicker/fuller and more straighter as well, just like in the movie. It really improves the look.
HTH
Mike
