Once you've logged-in to the CMS (see Accessing the CMS) you will see an overview of the project information below. On the lefthand side you can select between the projects you have access to, while the righthand side you can navigate through the different pages/sections of the project.
To navigate through the project content, click the Home Page Content link highlighted above.
On each page, you will see near the bottom two key sections - Child Pages and Page Files.
Child Pages are the sub-sections (or subpages) available from the current page, while the Page Files are the files/content to be displayed on the current page.
Once you click on Child Pages in the main Home Page Content section, you'll see a list of all the pages that appear in the main tab bar of the project, like the example below.
Pressing the Edit button on any page will toggle Edit mode. This will enable you to add/remove items, and drag-and-drop to reorder. You can click Save when you are finished, or Cancel to undo your changes.
When you navigate to a sub-page, an overview of the page settings and content will appear like the below. From here you can set the page name, whether it is published, the page type (layout), and the child pages or page files. An example is shown below.
Page layouts and how to upload/manage content (files) are covered in the next sections.