What is the correct order to connect and disconnect the jumper clamps?

For a negative-grounded system (most common), connect the positive (+) red clamp to the vehicle battery's positive terminal first, then connect the negative (–) black clamp to the chassis or a solid, non-moving metal component away from the battery. When disconnecting, always remove the negative (black) cable first, followed by the positive (red) cable, except for positive-grounded systems.