Turn all of the cards (clockwise) so you invert the four cards. You're still looking at the ten of hearts, you've only turned the cards upside down. This brings the aces on the other cards to the top.
As you look at the ten of hearts, take the top card, the double card with the ten on one side and the ace on the other, and simply turn it over so you’re looking at the ace and quickly place this on top of the other cards. .
Turn the cards so they are facing the spectators and spread the cards and show that you now have four aces.