I want to get back on differents part of the workflow

Hi
I have a workflow with differents functionalities that I would like the user could call every time she wants.
The workflow allows the user to make some customizable cleansing tasks on the data, and then she could make some other customizable analizes. I would like the user could get back on the cleansing or other analizes, without having to reset the workflow.
This is a part of the flow, and what I want is to could go on the flow and after every big square the user could get back on the previews ones. Like a link to the others.
Thnks