Effect: Two columns are created, a black one and a red one. Cards are drawn one at a time from the bottom of the deck and an audience member chooses whether to put it face down on the red or black column. The column colors are then switched and more cards are placed by the audience. At the conclusion of the trick, all the cards are flipped over and all the colors in each pile are together.
Step 1: Place two random cards, one black, one red, face up next to each other.
Step 2:Have the bottom of the deck facing you and draw the first red card, ask the spectator if they want it to go on the "Black" or "Red" pile. Place it face down on the pile they choose.
Step 3: If the bottom card is black, just tell the spectator you don't like that one, and place it on the top of the pile.
Step 4: Continue this practice with as many red cards as you wish. I usually stop when I run into a big section of black cards.
Step 5: Take out another red and another black card and place the black card face up on the "Red" pile and the red card on the "Black" pile. The "Red" pile is now the "Black" pile and vice versa.
Step 6: Take a few cards off the bottom of the deck making sure they are all black and ask the spectator which column to put it on. Remember to now move the red cards to the top of the pile in your hand.
Step 7: When you feel you have enough cards on the table (I usually strive for a total of around 12 - 15) take the very top face-up black card and flip it face down to the bottom of its pile. This puts it with all the other black cards.
Step 8: Square up the piles making sure not to mess up the order, and flip the the cards over in order showing the audience that they are all in color order. If you so choose you can have the spectator flip over the second pile. When flipping over the piles, just leave the face up cards face up, they will match the colors.