The Favorite Arguments window shows the contents of your favorite arguments list.
On the left is a tree which shows all the favorites folder and all its sub-folders. You can create a new folder using the File/New Folder... (Ctrl+N) command. You can move sub-folders to different locations in the tree using drag/drop or cut & paste.
On the right is a list of each of the arguments in the selected folder. You can control which columns are displayed by using the View menu, and putting a check against columns of interest.
You can move arguments to a different folder using drag/drop or cut & paste, or you can copy them to another folder using Ctrl-Drag or copy & paste.
To inspect an argument, right-click on it and select Properties....
Once you're finished managing the list, use the File/Save menu to save your changes.