Open a page from the page tree, with the "view" link of its row. A draft opens in edit mode; this is the way to reach a draft that was never published, which has no public URL.
Examples
When I open the page "Draft notes" from the page tree
When we open the page "About" from the page tree
And I open the page "Team" from the page tree
When open the page "Contact" from the CMS page tree
And we open the page "Home" from the page tree
Pattern
When(/^(I |we )*open the page "([^"]*)" from the (?:(?:django )?CMS )?page tree$/, …)
Part of @webship-js/django-cms-steps (github.com/webship/django-cms-steps), a step pack for Webship-js 2.0.x.