There are tons of Suicide Squad cosplay videos out there right now, but this is my favorite for the Enchantress. Not too difficult, looks amazing and only uses a handful of products. RayDoesFX only has a few vids on Youtube, but all are very good.
It is not in English, but there are some really good techniques to learn from this video without or without understanding it. Klaudia Utnicka has some really good Cosplay makeup tutorial vids on her Youtube channel. Check it out!