You can create a Test Identity Action through an Activity Diagram or a Modeler pane.
To create a test identity action through an activity diagram:
1. On the Activity Diagram toolbar, click the arrow in the split button that is to the right of the Accept Event Action button, click the Test Identity Action button, and then on the Activity Diagram, click in free space or within an Activity Partition, Interruptible Activity Region or Structured Activity Node.
2. Type the name of the Test Identity Action, and then press the Enter key.
Modeler creates the Test Identity Action and on it creates the First Input Pin and Second Input Pin input pins and the Result Pin output pin.
To create a test identity action through a Modeler pane:
1. In a Modeler pane, right-click the Activity or Structure Activity Node that is to own the Test Identity Action, point to New, point to Action Node, and then click Test Identity Action.
2. Type the name of the Test Identity Action, and then press the Enter key.
Modeler creates the Test Identity Action and on it creates the First Input Pin and Second Input Pin input pins and the Result Pin output pin.
Accept Event Action button, click the 
Test Identity Action button, and then on the Activity Diagram, click in free space or within an Activity Partition, Interruptible Activity Region or Structured Activity Node.