How do you make a cardboard combination lock?

To make a cardboard combination lock, start by cutting out a rectangular box from cardboard and creating a sliding mechanism for the lock. Use smaller cardboard pieces to construct a rotating dial with numbered slots and a corresponding locking mechanism inside the box. Assemble the components so that the dial aligns with the internal latch when the correct combination is set. Finally, secure the box and test the mechanism to ensure it operates smoothly.