How to get a Zwinky Card for free

You cannot legally get a free card. They are paid for.

It may be possible to earn one at various sites (i.e. PrizeRebel) which give rewards in return for some effort. However, I know of no such site that specifically awards Zinky Z cards.

Beware of people or websites which request your personal information in order to give you free money, items, or merchandise. Such are almost always scams.