In the vedio, he uses off camera dodging trick and video editing. First of all, he noticed that he changed the round paper disk with a white rubber ball when his hand were off the camera. Next, there were two things: a cubic frame and the other 2D flat strips, which you saw him removing from the floor. Here, he really has a 3D white frame. Later, he replaces it with white strips which are laying down on the pavement. If you watch the video closely, you can notice a mild break when he bends down towards the cube to remove one side of the cube. At that point two pieces of different videos were joined together. I will not say nicely because I can notice that difference. It seems to first time observer as mild jerk of camera man, but it is actually an editing point in the video.