This topic is what you're looking for, I believe. This comment will likely help too, from the Secretary Bird on Sara's website. If that doesn't help, say so, and I'll fold it and see what pictures I can post to help you out.
this is a confusing step, and describing it is not easy. essentially, you are untrapping the pleats that form the wings; think of it that way and try to arrange the layers appropriately, is one way to think about it.