My friend from church who has hair similar to Nicki's (same curl, same color, etc.) often wears her hair in this style. She says because her hair is so long, she can't put it in a ponytail, so she lots of times wears it in this bun style.
First, pull your Nicki's hair into a ponytail.
Then, pull all the hair up and find the hole that is in the center of the ponytail.
Smooth the hair over Nicki's head.
Then wrap your hand around it, squishing it into a bun.
Leave some curl around the bun.
Pull a ponytail holder over it, holding the bun in place.
Shot of the ponytail holder.
Smooth the curls evenly aroun the bun.
Puff it up, and there you have your hairstyle!