Preparation
Stack the deck so that the four aces are on top with three other cards above them. It really doesn’t matter what these three other cards are. 

Performance
Give the deck a false shuffle and have a spectator cut it. Next pick up the bottom cut half and in a relaxed manner push the top cut half aside to your left.

Deal two poker hands, one to the spectator and one to yourself then place the rest of the cards near the cut packet and as you both pick up your hands to look at them, casually pick up the cut packet and put it on top of the other one.

Ask your spectator how many cards he wants to draw. If he says three then deal him the three top cards but if he can’t make his mind up or wants less, take a look at his hand and advise him to take three. At your turn you discard four cards and draw the four aces!