It is possible to use the 'Create New Folder' button in the Action Toolbar to create a new folder within a standard asset folder.
The Folder Properties popup will open and you can then give it a name, apply a metaset (this is what the assets will be tagged with) and you can also add a description that is output on the folder when saved.
Custom Metadata
Some pages, like the Showcase Accordion, support Custom Metadata. Here you can choose the correct option and add an image and a title to display on the parent page.
Advanced Options
Search Keyword: Here you can add a keyword to the page. Please separate keywords by a comma.
Sorting of children: If the page has children here you can control the sort order of these pages. If User Selected is used, the sorting will be based on the user's selection during the session. If using Custom, you can click and drag the options to re-order.
Publish date: It is possible to set a date at which you would like the page to be published. The page will only be visible to system administrators until this date.
Visibility: You can choose for the folder to be visible to everyone or only for System Admins. This is useful when a folder is being worked on and it is not yet ready for users to see the content.
It is possible to create a DAM Folder via the Page Admin Bar - see more information here