One on each prong of the plug, and then one to power and one to ground.
ALWAYS verify your power First. pull down the plastic/rubber insulator sleeves so the alligator clips can't touch, and off you go.
Been doing it that way for over 20 years. On 460 I look for a 120 control circuit inside the unit or run an extension card.
With romex you can run 250 feet. <g>