Place pages in menu system
First, any page that should appear as a link in a subnav, should be added to the menu system.
Add subnav to page
Then to add the subnav to a basic page, click on Edit tab, and configure under Subnav setup on right side.
Use the settings below. The Fixed Parent Item will be the same for all pages in your subnav. (Unless you have a subheader in your subnav.)
