When you're at the beach and you leave your thongs (or sandals) while swimming, the sun can quickly heat them up and burn your feet when you put them back on. Redditor shawbin suggests turn them upside down so they don't absorb the sun's excessive warmth and are comfortable to wear later on.
Photo by Hirug (Shutterstock).
Sometimes even the sand is too hot, so commenter and Arizona-native shawbin suggests a slight modification of this tip:
A better way to do this is rest one face up and the other face down on top of the first. This way neither of them are exposed to the hot sun or the hot ground/sand.
You can always dip your thongs in the water to cool them off a bit faster as well, though that's a pain in terms of attracting extra sand.