The performer begins by displaying a colouring sheet image that has not been completed. The performer then offers a spectator several pens/pencils/crayons (Red, Blue & Yellow). The spectator is instructed to mix these colours, then to take them one at a time and begin to colour certain parts of the colouring sheet image. While the performers back is turned so that he cannot see what colour has been selected.
Once the spectator has finished colouring in the image it is displayed for all to see, the perform next reveals a prediction that was made before anything took place and that has been in full view throughout. The prediction is a perfect match.