Find the Superflow Toolbar and click the More Options icon

A sub-menu will expand, click the View Project option to select
A new tab will direct you to the Project Dashboard page
Click the USERS module to access the Users page

Find and click the + Invite Users button

The Invite Users dialog box will appear
Click the Drop-Down menu and select Commenter

Additional fields will appear

After entering and defining the required credentials, click the Send invites button