To create a folder or subfolder, select "New Folder" on any page. A pop-up will appear. Name your folder something descriptive.
Access your folders from the Organize & Share Folders tab. Note that the small drop-down menu is for moving items to folders; you cannot navigate to folders from here.
You can access references by folder from the "View" menu at the top.
or from the side tab
From the Organize & Share Folders tab list you can rename, organize, share, clear, or delete folders. You can adjust sharing settings by folder, view sharing statistics, and see which references are not yet in folders.
Note that you do not lose your references when you clear (empty) or delete a folder, and that you cannot rename or delete the Last Imported folder.