You say: “Just follow my lead and copy what I do”
Spread out your own pack face down in a ribbon. Take a card from the middle and look at it saying you’re going to memorise it (you don’t need to in fact!)
Next, you say: “Now you take a card and look at it”
Take your face-down pack, square it up and put your chosen card on top face down.
Ask the spectator to do the same.
Take your cards and cut them so that your chosen card disappears in the pack.
Ask the spectator to swap packs again.
Tell them to take from your pack the card they memorised and put it face down on the table.
Spread the cards out on the table, face up and towards you and look for the card that you glimpsed at the beginning of the trick (eg. 5 hearts).
When you’ve found it, the card underneath it will be the spectator’s chosen card.
Take it out, put it face down in front of you and ask the spectator to show their card.
They turn over their card….You pause and then turn over yours.
They’re identical.
Now you can say: “You really did do as I did!” or “You really did follow the leader!”