Unplug the power wire from the socket. Tap the lower metal ring counterclockwise using a rubber hammer. As you tap it, a metal lip on the lower ring will disconnect from the top metal ring.
Pull the unit from the bottom of the sink. Remove it slowly because water and food in the disposal can leak out.
Dispose of the water and food and place the disposal on a surface that is flat and that you don't mind getting water and food on. Remove the screw securing the clamp and the metal door on the bottom of the unit with a screwdriver.
Pull the door off the bottom of the unit and remove the screw that is securing the green wire to the frame using a screwdriver. Turn the plastic caps on the red and white wire counterclockwise and pull them off the wires. Pull the red and green wire connected to the cord apart from the wire connected to the unit.
Place the wire into the clamp and reconnect the green wire to the frame and the red and white wire to the corresponding colored wire on the unit. Place the plastic caps over each wire once they are connected and turn the caps clockwise until tight. Replace the unit to the sink the opposite way that you removed it.