Yes, this is completely possible. For example you can use the Rabix composer tool to map out the nodes and connections. This gives you a visual depiction of the workflow, which you can then export to json CWL representation.

The best way to do it is to load the workflow using Rabix Composer (http://rabix.io/) as you can both see the graph and edit (add or remove steps).

The cwltool (https://github.com/common-workflow-language/cwltool) also has some options to print a visual presentation of the graph. Here's something from the tool help

 --print-rdf           Print corresponding RDF graph for workflow and exit
 --print-dot           Print workflow visualization in graphviz format and exit