2. Map out your main path

Keeping in mind the 2 to 3 points you want to focus on, map out the main backbone of your story or case.

Try not to get too distracted by details and sidebar issues at this stage. You can come back to them.

For some authors, it is sometimes helpful to break your story into, say 5 simple blocks:

1. Describe your setting and patient
2. What is the first challenge or decision point to pose to your learner?
3. What is the second main point, tip or puzzle?
4. What is the third key point you want to raise?
5. How are you going to wrap up your case and summarise?

Get those main blocks down first, tie them to your key points, and build on that backbone.

At this point, you might want to consider using a wizard to map out these steps. The Linear Case Wizard is nice and easy to start with. 

Select the approximate number of nodes you think you'll need to start with. (You can add many more later. You only need enough to jot down your main points just now.) The wizard will expand to accommodate the number you need.