Step by step execution
To start step-by-step execution, place a breakpoint on the element where execution should stop first. After Designer stops on that element, click the 
Next element button. Designer will move from one element to the next and show how the strategy is executed step by step.
To enter a Composite element, wait until step-by-step execution reaches it, then click 
Step in. The next step will be executed inside the Composite element. To leave the Composite element, click 
Step out.