Start by showing a classy looking frame with a red silk on each end and a white silk tied between the two red ones. Untie the silks and vanish the white one using your choice of methods.
Finish the routine by placing a white balloon in the frame, and with a magical gesture, the white silk is once again tied between the red silks. All the necessary silks are supplied and you'll get 10 balloons to last you a while.