Using the ChargeCard USB cable is a breeze. Just plug the standard USB plug into a power source or your computer, and connect the 30 - pin end to your iPhone 4/4S. When not in use, you can easily store it in your wallet due to its credit - card size. For safety, make sure the power source is stable before plugging in. Avoid bending the cable too sharply as it might damage the internal wires. To keep it in good condition, gently wipe it with a dry cloth if it gets dirty. That's all you need to know to make the most of your ChargeCard cable!