You can add new folders to the basic catalog structure and add subfolders within those folders.
To add a folder to a catalog
Open a catalog.
In the Owner drop-down menu, select the owner of the catalog that you want to open.
Select the catalog or folder in which you want to add a new folder.
Right-click the item selected in the previous step and select New Directory. A folder called New Directory is added. If you want, you can rename it.