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I'm not sure how orienting the card that is on your own head would help. You don't know what it is.

That being said the method of "Bob always tells the truth, Alice lies" is sort of a card orientation way for two people. Alice puts her card up sideways and Bob knows that to mean he should tell the truth. Likewise Bob doesn't rotate his and Alice knows to lie.

However that only works with two people and they have opposite spins.

Maybe it can work with more than two and you have two rounds of guessing. Also you need to know that you have differing spins.

You orient the card based on the other player's card, for their benefit. That's why I think it would be against the rules - it's the same as if you held up fingers or made a face, it's communication.

Bruce and Ava decide to put the card horizontally if they see a red card, or vertically if it's black. If Bruce sees a vertical card, he knows Ava sees a red card on his head.

In the game of four, the players decide one of them will guess, and two others will communicate information in binary:

horizontal, horizontal: hearts

horizontal, vertical: diamonds

vertical, horizontal: spades

vertical, vertical: clubs

However this latter method only requires three players, not four. But it is similar to how professional bridge players cheat, by communicating their hand (which is hidden from their partner) with secret signals: http://www.newyorker.com/magazine/2016/03/07/the-cheating-pr...

Wow, thanks for that link about cheating in bridge. Spent hours going over that and stories on http://bridgewinners.com/

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