This 6 foot ground cord plugs right into the USB port and makes contact with the laptop’s chassis. The other end plugs into a grounded wall outlet (North American plug style). Simple and effective, as recommended by Michael Neuert.
Make sure to use an outlet tester to check your outlet for proper grounding if you have any doubts about the wiring job of the outlet you are using! If the outlet is not wired properly then the grounding will not be effective.