When creating a workflow in SharePoint Designer 2010 it is difficult to document each step, but if you have access to Visio Premium then the process is relativly simple.

in SharePoint Designer 2010

1. export the Workflow to Visio
2. close the open workflow
3. open Visio and start a new SharePoint Workflow diagram
4. click the import from SharePoint
5. select the exported workflow from step 1
6. add all comments by double clicking each object
7. export the diagram to SharePoint
8. select the imported file
9. select the update option
10. in SharePoint Designer click the import workflow
11. select the updated workflow

All the updated information should now be visible when you edit the workflow.