Using the Shock One massage gun is easy. First, make sure the battery is charged. Then, turn it on and select the appropriate intensity for your needs. You can use it on different parts of your body like your legs, back, or shoulders after a workout. When using, move the massage gun slowly across the muscle area. As for precautions, don't use it on injured or inflamed areas. Also, don't use it for too long at one spot. To maintain it, keep it clean and dry. If the battery runs out, charge it with the provided charger using the 5V charging voltage. That's all you need to know to get the most out of your Shock One massage gun.