It seems that seasoned professional interaction designer also does it. They gathered for 4 days. And they worked hard 9 to 5 to produce a interaction design which is wireframe model. There is two main course in the Cooper U, which is interaction design workshop and UX bootcamp. I attended design workshop, and I hope to attend UX bootcamp. Although it is quite expensive, I think it's worth every penny. Also this UX bootcamp was held on the Allen Cooper's farm house.