Might get drunk and lose a finger, but I’m trying it.
Step 1 – Grab a beer bottle preferably with thick glass such as Corona bottles. Tie a string just above the label on the empty bottle
Step 2 – Keep the string tied and soak it in lighter fluid
Step 3 – Put the string back on the bottle and hold it horizontally. Light the string rotating the bottle so the flame spreads
Step 4 – After you hear the crack, pour cold water on the string and the top of the bottle will fall off
Step 5 – Now grab sandpaper and sand the edges of the bottle till it is smooth