Creating links between instances on an object diagram
You can create links between Instances only when their associated classifiers are linked through an Association or Aggregation.
To create a link between instances on an object diagram:
1. On the Object Diagram tab, click the 
Link button.
Link button.2. Click the source Instance, that is, the Instance whose classifier is the source Class, Data Type, Interface or Signal for the Association.
3. Click the destination Instance.
4. If you want to show the nesting through containment, drag the nested Instance on to the nesting Instance.
Modeler creates the link on the diagram, and on the source Instance, sets the Linked Value of appropriate Slot to the destination Instance.