I started by making a few parts along the front and sides of her hair as shown below in the next 4 pictures
I put the remaining center hair into an elastic.
Below is the parts on the right side of her head.
Below is the parts on the left side of her head.
Next I took the hair on her right side above her ear and wrapped it around the ponytail.
Then I took the hair on the front of her head and rolled it as shown below then I wrapped it around her ponytail.
On the left side I took her bangs and swooped them toward the side before I started rolling that hair and securing it around the ponytail as well.
Then roll the hair just above her ear and attach it to the ponytail.
I used bobbie pins to make the messy bun lay flat to her head. I also added a pink ribbon that I wrapped around the ponytail and tied in a bow at the bottom.