I talk to my Protagonist and ask them what they would change in their lives. If that thing seems to be environmental then there ya go but if its caused by another person, for instance Tenyane Queen of the Fae having her twin sister killed and forced to run to the human world so that The coop cant actually kill her and maybe she can find a way to get her throne back led to Maurelle, the queen's distant cousin. If she had been born a boy would have become the queen's consort. Instead she had no power no real title and decided to fix it by taking over the world as she knows it. Her father died young, her mother gave her everything she wanted all while saying she spoiled her because it wasn't fair that her gender kept her from having a throne of her own. Humm... Kinda makes you wonder what would have happened if the queen had been a king and her cousin a boy as well.