1. First, prepare all the necessary materials.
2. Then, put one end of the paper core on the cup and draw the shape with a pencil.
3. Then, cut out the drawn shape.
4. Then, draw the shape as shown in the figure on the winding core with a ruler.
5. Then, cut out the shape drawn on the roll paper core with a utility knife.
6. Then, put the paper core in the hole of the cup and stick it with glue.
7. Then, glue the two paper cups as shown.
8. Then, cut a small opening at the other end of the paper core to facilitate the charging cable to pass through.
9. Finally, we can see that the small manual production of turning waste into treasure is completed and the problem is solved.