An interactive website from 2016 (or possibly earlier?) with overviews of each chapter, sample downloads and interactive tools:
In order for action to occur between two people, one person must make a request or an offer to get things started. If no one makes a request, or no one makes an offer, nothing is going to happen between them!
Once a request or an offer is made, then the ball is on the other person to determine what happens next, and so forth, until the person making the request, or accepting an offer, is satisfied.
This playground will let you select the action of the customer or performer by letting you click the circle that represent the actions.Just try it out to get the flow. For example, after a request is made, typically the performer will agree to it, but she may also counter-offer or just decline it.
If you engage with the tool, we would appreciate your feedback