You can navigate to
- higher level BPMN diagrams
 - related Process diagrams
 
To navigate to a higher level BPMN diagrams
- At the bottom left corner of the diagram pane, on the toolbar, click the 
 button and select higher level BPMN diagram. 
To navigate to a related Process diagrams
- At the bottom left corner of the diagram pane, on the toolbar, click the 
button and select related process diagram.