Supporting Documents allows you to not only upload pdfs or images, but also create additional documents from within the app.
You can create supporting documents or attach files from both the resources tab within the agenda item or directly from the meetings folder view
Within an Action
From an action, you first want to click on the resources section. Once in the resources section you can upload files to attach or create a new supporting document.
When viewing an agenda simply click on the paperclip icon next to an agenda item. This will expose where you can upload files or create new supporting documents.
To work on a supporting document simply click it's name and the document will open.
You can make any supporting document a template by clicking the file menu and choose "Save as Template". This will create a new template with the name of the current document. You can always change this name from the settings of the application.