Make cups out of bottles! 5 easy steps! by Make cups out of bottles! 5 easy steps!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 sting rotating the bottle so the flame spreads. You should hear the bottle crack slightly in about 10 seconds.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.