The performer request the help of two volunteers, handing out to each volunteer a blank face card. He then request each volunteer to mentally picture a playing card of their choice ( a truly free choice), to look at, and the concentrate on the blank face card that they just received. The volunteer on the left thinks of any red card and the one on the right thinks of any black card.
The performer then takes two other blank faced cards and proceeds to write down a prediction on the blank side of each card. He places the two prediction cards onto a card stand, backs to the volunteer/audience, and faces towards him.
The magician then asks the volunteers what card each thought of. He (or the spectators) then removes the two cards thought of from the deck, and the performer places them onto the card stand next to the prediction cards...
Upon rotating the card stand, the magician's predictions are found to match the volunteers' thought of cards!
This effect can be done in a living room or for a much larger audience