On their wedding night, the young bride went up to her new husband.

"Since we're married now, we can arrange our sex life like this: In the evening, if my hair is done, that means I don't want sex at all. If my hair is somewhat undone, that means I may or may not have sex. And if my hair is completely undone, that means I want sex."

"Okay sweetheart," the groom replied. "Just make sure, when I come home, I usually have a drink. If I have only one drink, that means I don't want sex. If I have two drinks, I may or may not want sex. But if I have three drinks, your hair doesn't matter."