Twist Earrings

You need a peen hammer, a stake, a couple of pliers and a crescent shaped sheet of metal (brass, copper, aluminum, silver, iron) about 1 mm thick. 
Start hammering the outer edge of the crescent, halfway you'll find you must reverse it. Go on hammering the whole lenght of the outer edge.
Now take the two extremities of the wriggled shape and pull straight.