When a workflow is created in the Central Workflow area for documents, it will then be available in the document management workflow screen. For example when a document is scanned and uploaded to a client a workflow can be attached and be sent to the client partner to review.
File > Maintenance > Document Management > Workflows.
Select a Source from the drop down.
Select a Library from the drop down.
Select a Type from the dropdown.
Using the arrows move the workflow from Is not available section (on the left) to the Is available (on the right).