Lay two doors on a flat surface and line up the sides. The doors need to be identical in their measurements, although they can be different colors or styles.
Place three hinges along the seam where the doors touch, then screw the hinges in place using a drill and 3/4-inch long screws. The hinges need to be spaced equally apart for functionality.
Turn the doors over and lay them flat, then place a third door along one side of either door. If you are using alternating colored doors, place the third door next to the one that is colored differently. For example, the color could be red, white and red.
Place three hinges along the seam where the two doors meet, then screw the hinges in place using a drill and 3/4-inch long screws. Again, the screws need to be equi-distant.
Screw a rolling track knob onto the upper-right, lower-right, upper-left and lower-left edges of the movable wall. Position each knob 2 inches from the corners, facing upward or downward, respectively.
Insert the movable wall into a track for use.