@SarahKroeger I can't really help you from her. but I'll try. sorry bout the late response. I was eating.
go to create. and click add story. after that title your story. pick out cover. speaking of which, I need to change mine. anyway, after you do that you can start writing. when you are ready to publish click the publish button. then you can add another story part there is a plus sign at the top that will let you add another story part.
hope that helps. peace out.ø