Your Subpage templates allow up to 9 content sections and 5 sidebar sections (sidebar sections only display on the Subpage Default template). Each section can contain text, images, etc., and then added to a page under the "Sections" area of your page settings.
Go to Content > Sections
Within the sections module, the following fields are used:
Content - This is the main content block and supports the content/styles of the page content.
Background Color - This color allows you to set the background color of the section and should be a html hex value. A good reference is http://www.w3schools.com/tags/ref_colorpicker.asp.
Background Image - This serves as the section background image. This image should be 1,400px in width by the desired height. The height will depend on the amount of content in the section. A recommended height would be between 600px and 1,200px (double for retina).
Dark Background - Selecting this checkbox displays the content in white color on top of the site default section background color or dark background image.
Large Padding - Adds additional horizontal padding to make the container taller.
Narrow Container - Displays the content at a narrow width.
Parallax Background - This option turns the Background Image into a parallax background.
Icon Class - Selecting the page checkbox "Section Nav" will place a section navigation at the bottom of the page on mobile devices allowing users to scroll between sections. If this option is used the section "Description" field will be the name of the link and the "Icon Class" field is used to add a custom icon to the link. If the page checkbox is selected, only sections with the Description field used will display in the navigation.
See full list of available icons here: http://mk041.monkpreview.com/_assets/fonts/icons/icomoon/