A bewildering way of a "Do as I do" routine!

Magician shows a red and blue Deck. The magician passes a Deck to the spectator.

Both the magician and spectator looks at the face of the Deck and the back of the Deck. Next, both parties shuffle their own Deck and then choose any card from the Deck to put it face down on the table.

Magician cuts the Deck into smaller packs and spectator can say stop at any time to put their red face down card into the blue Deck.

The spectator also follows the same routine by cutting the Deck into smaller packs and the magician can say stop at any time to put the blue face down card into the spectator's red Deck. Next, both parties swap the Decks.

Finally, both the magician and spectator both spread the Deck and take out the only different distinct card in the Deck they are holding. Upon revelation, both cards match each other!

No gimmick Decks used
No forcing of card selections
No rough and smooth
No misprinted cards
No sleight of hand
No memory work required
Easy to perform