Loose curls (with material)?

I've heard, adn seen, that you can make your hair curly by putting in bits of material when its wet at night.my friend's gran uses stockings, and when you wake up and pull the stockings out you ahve loose curls.I want to know how to do this.my hair is naturally very curly, and it corkscrews, which is fine, but i'd like to try it this way (then i dont have to gel it etc etc), or if anyone has any other simple ways to create loose curls, could you tell me?that dont require curling irons..or rollersLoose curls (with material)?
take small sections of wet hair and twist them into knots. then tie them up with strips of fabric.