Keeping the towel at arms length, move it into the center of the flame and allow it to catch on fire. Continue to hold the flaming towel at arms length to minimize any chance of burns. As the Flame subsides, snuff it out with a quick jerk to avoid catching the towel on fire. To avoid burns, the flaming towel must be handled with care. Combustable material must be removed from the vicinity, and a fire extinguisher should be available.
Isopropyl alcohol can damage the eyes severely.