The cardholder's signature is a proof of consumption. Credit cards originated in the United States, and you can swipe your card by signing in the United States. If the signature is inconsistent with the signature of your reservation bank, the consumption is not established. In China, most people use passwords and signatures. Actually, it's mainly a password. Everyone doesn't pay much attention to signature, so even if you cross the line, the cashier won't care about you. So it doesn't matter what you sign.

But I suggest you use your ID card to apply for a credit card. It will be troublesome to use someone else's. What happened? This will be a big event!