Diagramming Action in Stories: The Actantial Model
Diagramming action helps sort out different story elements. The actantial model highlights the distinct roles played by different elements in the story. In this diagram, you can see that each role is played by a different character. That need not be the case. The hero's courage can be her helper; her self-doubt can be her opponent. She may be sent by her desire to make the world (receiver) a better place in some way (object).
The actantial model provides an alternative to the well-known linear conflict-resolution plot structure I primarily rely on. (Check out my talk about that model, beginning about 10 minutes into the video.) I derived my diagram from this page.