You don't have to take a class, especially with your applique experience. I had never done it before and had an awful time trying to learn out of a book (and I have several!) I got Nancy Chong's DVD which, to me, was worth it's weight in gold. One website that might be helpful and has step-be-step instructions is:
http://www.quiltshawaii.com/howtosub.html
Because I am still fairly new at Hawaiian Applique' myself, I use 100% cotton for both layers. The first one I tried (because I didn't know any better) was batiks and I failed miserably. It was too difficult at the time. For me, the batik did not fold easily with needleturn applique' and I got too frustrated and didn't even get as far as the quilting part. That project is folded neatly in a drawer until some other day.
I recommend using 100% cotton for your first project or two until you get the hang of it. I did on my second project and was hooked. Even though I enjoy machine quilting, I seem to always have a "hand" project going at the same time.