You can’t fit a towel inside them or air-dry (the water only condenses and becomes trapped, eventually discoloring the glass). Try this: Tightly roll a paper towel, and insert it 3/4 of the way into the bottle; it will absorb the moisture.
Unknown - Source of both the Trick Description and Trick Image are unknown
Is this trick using work of your own without attribution? Click here to PM the user
and let them know!