Phew these are pricey (and I'm not a fan of Glinda's version), however, this provides good images to go off of to create your own Wicked Witch of the West/Elphaba costume. Wouldn't have thought about the black skull cap for example. | Disney Store Limited Edition Wicked Witch of the West Costume for Adults (Pre-Order) #DisneyOz.
I love this Witch!
How to Train Your Dragon #Cosplay | Ichibancon 2014