I wasn't sure exactly how I wanted this to look so I pinned everything to the hat first to get an idea. Then I took a photo to remember the arrangement. Deciding how you want it is the most time consuming step.
I used a hot glue gun to first glue down the lace trim around the crease in the hat, making sure to also glue down all the little bits so it didn't flop around.
I then glued the flowers and feathers on, followed by the buttons. And... voila, fini!!