2. Practice: Prepare several complete beer bottles. If there is a sticker on the surface, tear it off yourself.
Tie an empty beer bottle, preferably with a thicker glass bottle. Tie the rope a little above the bottle label. Take out the rope after knotting and immerse it in a lighter liquid.
4. Put the rope back on the bottle and hold the bottle horizontally. Light the rope, turn the bottle and let the fire burn along the rope. After about 10 seconds, you will hear the glass break slightly.
After hearing the crack, pour the ice water on the rope and the bottle cap will fall off. Now you can take a piece of sandpaper and smooth the edges.