Create Content in a Blank Page

The Sub-Process function allows you to create sub-processes in a new blank page.

Using the "Create Content in a Blank Page" function in the "BPMN" ribbon

Navigate to the "BPMN Diagram" panel and click on the Create Content in a Blank Page while having the Sub-Process shape selected.

create content in a blank page

This will create a new blank page for the selected sub-process.