Candle wax and crayon respond well to ice. Fill a plastic bag with ice cubes, wrap it in a towel, place it on the stain until it hardens; carefully coax wax off with a plastic spatula.
The theory was first published in 2005 a press released under the name of Cliff Arnall, who at the time was a tutor at the Centre for Lifelong Learning – a Further Education centre associated with Cardiff University. Later, however, the Guardian printed a statement from the university distancing itself from the psychology professor: "Cardiff University asked us to point out that Cliff Arnall.