1. Prepare the plastic bottle caps that need to be punched. If there are many bottle caps, you can classify the bottle caps by color, as shown in the figure.

2. Then prepare awl and lighter, as shown in the figure.

3. If it is inconvenient to use a lighter, you can use a candle, heat the awl and directly cap the bottle. Pay attention to the back of the bottle cap, so that the space in front will be more rounded and look more beautiful.

4. Finally, you can punch a very neat and beautiful hole in the bottle cap, as shown in the figure.