How to create a shortcut to a folder to Documents

Open terminal and ln -s /media/sf_fedora ~/Documents/sf_fedora would create a symlink in Documents folder.

If you're using Nautilus, it has a dedicated mouse+key combo for creating symlinks:

Ctrl+Shift+drag

Alternatively, you can use either middle (wheel) click drag or Alt+drag to get a move/copy/link menu.