What will happen if I sign up for a credit card and let my family member use it instead?

Legally, it is not allowed.

However, we can print whatever name we want on the card, so you can tell the cashier that that is your card name. The police will come in if the original card owner make a report.

There should be no problem but it could attract some technical problems.

The cashier has the right to verify the owner (although many many times they no longer do that unless there's a fraud or something recently in that shop).

more Troubles if you let someone used your card overseas and issues arises then it might be even headache

There's actually no issue with that, but I would be around to physically swipe the card so that I know what's going on it. And of course he has to pay me back the money.

My brother (who is still studying) recent bought a new phone because the old one was dying. I could have gotten a supp card for him but chose not to, in case he lost it or something. So I was around to swipe the card when he bought his new phone, and took back the card there after. A little hassle of course, but nothing too major. In time to come, he will get his own card and I will pull him to the miles camp.

Then again, I'm probably more guarded that other when it comes to such matters. To me, having a supp card still means that I have to pay whatever is put on the supp card, and the last thing I need is a bill shock.

For a self employed, a credit card can still be obtained with a pledged collateral. So try going down that route first.

I dont think there is any issues. Because the credit risk in the event of default is undertaken by you too. To the credit card company, they do not see any change in credit risk which is detrimental to them. As mentioned by some in this group, you can also consider giving that individual a supplementary card.