A plot structure map is just another way of saying an outline, but you do it in a lineal manner. Begin with your main character and make a series of little boxes that contain the highlights of what is happening to him or her. Then interconnect the boxes with the other characters in the story, and use little arrows to lead you from one box to another. It’s especially helpful to use the plot structure map format if you have a story with a number of characters in it, if you are doing lots of flashbacks, or if your story covers a lot of geographical sites. It’s one way to make sure you don’t have someone pop up in Peoria when you left him stranded in Timbuktu.