To jump-start a car battery, follow these steps carefully:

1. Prepare the vehicles and equipment
   • Park the car with the good battery close to the car with the dead battery, ideally within two feet, either nose-to-nose or side-by-side.
   • Turn off both vehicles and engage the handbrakes.
   • Make sure both batteries have the same voltage (usually 12 volts).
   • Get jumper cables or a jump-starter kit ready

2. Identify the battery terminals
   • Open the hoods and locate the positive (+) and negative (−) terminals on both batteries. The positive terminal is often marked with a plus sign and may have a red cover; the negative is marked with a minus sign and is usually black

3. Connect the jumper cables in the correct order
   • Attach one red clamp to the positive terminal of the dead battery.
   • Attach the other red clamp to the positive terminal of the good battery.
   • Attach one black clamp to the negative terminal of the good battery.
   • Attach the other black clamp to a grounded, unpainted metal part of the car with the dead battery (such as an engine block bolt or chassis), away from the battery and fuel system. Do not connect the last black clamp directly to the dead battery’s negative terminal to avoid sparks

4. Start the cars
   • Start the engine of the car with the good battery and let it run for about 1 minute to charge the dead battery.
   • Then, try to start the car with the dead battery. If it doesn’t start immediately, wait a couple of minutes and try again

5. After the jump start
   • Once the dead car starts, let both cars idle for about 10 minutes to allow the battery to charge.
   • Carefully disconnect the jumper cables in the reverse order of connection (black clamp from grounded metal, black clamp from good battery, red clamp from good battery, red clamp from dead battery).
   • Keep the jumped car running for at least 20 minutes or take it for a short drive to recharge the battery fully

Safety tips:

• Ensure no sparks or flames near the battery.
• Avoid touching the clamps together when connected to the batteries.
• Wear gloves and eye protection if possible

This method is widely recommended by automotive experts and organizations for safely jump-starting a car battery