How does Nikon D700 shoot multiple people with multiple exposures?

A piece of black cardboard and a tripod will do. For five seconds on TV, the model posed and pressed the shutter for one second, and then black cardboard blocked the camera for three seconds. Within three seconds, the model can change the position and posture, then open the cardboard and expose it for another second, and it is finished. Remember to set two levels of overexposure, otherwise the picture will be very dark.