This works better with older vehicles that have more metal on them, but if needing to jump start a vehicle that is stopped on the shoulder of a busy freeway (or other location), and there is no way to get alongside, or make a u-turn to be nose to nose, park close behind the disabled vehicle, separate your jumper cables, connect them together, and connect them to the positive terminals on both batteries. Then use your crowbar (you do have one of those, correct?) to touch both metal on both vehicles. That will connect the circuit, and you should be able to now start the disabled one...