Once you have established your protagonist’s Ordinary World, you then move to the Call to Adventure. This is the first turning point, so to speak, in your story because it is the point at which your heroine encounters a problem. The problem puts your heroine at a point of decision. Will she accept the Call to Adventure or will she choose to remain in her Ordinary World?
If she chooses to remain in her Ordinary World, you won’t have a story. 🙂 In order to have a story, your heroine must accept the Call to Adventure, although she may hesitate at first or do so reluctantly.
The Call to Adventure reveals the heroine’s goal and sets up the stakes she will face in meeting that goal. The Call to Adventure is also referred to as the inciting incident.
Think about your protagonist’s Call to Adventure. What is it? What forces her to make a choice to leave her Ordinary World? Why should she leave her Ordinary World? What is at stake for her if she does not? What are the gains for her if she does? What dangers will she have to face along the way?
Here is a useful link that structures the Hero’s Journey into acts: