Make sure that the batteries in both cars are the same voltage. You won't find many six volt batteries around anymore, but there's always the chance. The voltage will generally be stated on top of the battery, or look in the owner's manual.

• The cars should not be touching, and both ignitions should be off.
• Each battery has two metal terminals on it. One is marked positive (+); the other is negative (-). Attach one end of one cable to the dead battery's positive terminal.
• Attach the other end of the same cable to the positive terminal of the battery in the starting vehicle.
• Attach one end of the other cable to the negative terminal of the battery in the starting vehicle.
• Attach the other end of that cable to the engine block, or frame, of the car with the dead battery. Look for unpainted metal surfaces. Do not attach the negative cable to the dead battery itself, and do not attach it to the frame anywhere near the battery.