I feel like this was pretty obviously meant to be a gag and it succeeds in that.
Suggestion tell spectator to name a card and that you can guarantee you have that card in your
sock. They name a card. You pull out a a deck inside one of the socks. Take the cards out of the
deck and wait for a few beats four laughs. The deck is of course an invisible deck. Ask what card
they named again and proceed with the invisible deck as normal.