With Attachment Point
WARNING: This page is about a different car, the 2009 Dodge Caliber. However, it is still accessible from the selected car via links, so may be relevant.
For detachable tow bar pass the cable through the attachment point and clip it back onto itself.
For fixed ball tow bar attach the clip directly to the designated point. This alternative must be specifically permitted by the trailer manufacturer since the clip may not be sufficiently strong for use in the way.