The performer introduces a small envelope and says that there is a
playing card inside. He places the envelope on the table and never
touches it again.
A participant takes the deck out of the box and shuffles it. Then they
cut the deck and the top card is immediately turned over. It is, for
example, the 7 of Spades. The deck is turned face-up and clearly spread
to show that there are no duplicates.
The participant opens the envelope and removes the card inside. It is a
perfect match - the 7 of Spades.
AND THERE ARE NO OTHER OUTS - the card in the envelope is ALWAYS the
card they choose!
NO sleight-of-hand required. This literally is as easy as it gets!
Alternative endings: You can have a photo of the card posted on your
Twitter feed, Instagram or other social media. Or you can WhatsApp or
message them at the start and they check the message at the end.