Streching: helps to elongate curls from shrunken state. Can help with styling versatility.
Below are a few ways to stretch:
Bantu knot
Braid/twist
Threading
Bunning
Banding
hair clamps
Resources:
http://blackgirllonghair.com/2012/10/3-ways-to-gently-stretch-natural-hair-without-heat/
http://www.naturalhairrules.com/african-thread-to-stretch-natural-hair/
http://luvtobnatural.com/hair-tip-tuesday-stretch-your-hair-without-heat/
http://www.thenaturalhavenbloom.com/2013/07/could-stretching-natural-hair-be-harmful.html