Creating a new diagram
1. In the Packages pane, right-click the Package in which you want to create the diagram.
2. Select New > Diagram, point to the appropriate submenu, and then click the command for the diagram type you want to create.
Modeler opens the new diagram, which in most cases will be blank.
Alternatively:
1. Select the package in which you want to create the diagram.
2. On the Home tab, click the arrow next to New diagram type and then click the option for the diagram type you want to create.
You can also create new diagrams based on the configurations and styles of a previously created diagram. For more information, see Setting up default view options and compartments for new diagrams.
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You create an Activity Diagram through the context menu of the Activity that will own it.
You create a State Diagram through the context menu of the State Machine that will own it.