This is a fun way to add a little more to your ponytail.
First start by making a square part on the top of her head. Make a french braid along the back of the square. *shown below*
Then make a french braid along the front hair line parallel to the first braid.
Put all the hair except the front braid into a ponytail secure with an elastic. Then wrap the front braid around the ponytail. Secure that with bobbie pins or a clear elastic.
Below is the top view.
Below is the side view.