The 16-year-old started the design in Term Two as part of her NCEA Level Two internal.
She said her inspiration came from a design she found on Viktor and Rolf's Spring Summer Couture Collection, which she fell in love with.
"I knew I wanted to make a coat so I just searched around some designers and found one from Viktor and Rolf and I adapted the patterns and changed them."
Miss Hollings-Hatton said the experience on the catwalk, which some of the world's top designers and models had walked on, was "amazing" but also pretty scary.
Her strategy was to look straight ahead.
"I went to the World show the night before so I had an idea, which was good, and I wasn't wearing heels which also made it a lot easier."
"I got really nervous beforehand but once out there it was not as bad as I thought."
Miss Hollings-Hatton has always had an eye for fashion and she hoped to keeping going with a goal to be a fashion designer in the future.
She said 'Walk The Line' opened her eyes to the real fashion world and showed her how much it took and what she needed to do to make it.
"It has kind of upped the ante for me wanting to do something like that again."
Her mother Clare was in the audience during the competition and described it as an exciting but nerve wracking time.
"She had put in so much work and it was an amazing opportunity for her being able to see and meet lots of people in the fashion world."
Napier Girls' High School student Frankie Alexander-Kemble was also in the competition modelling a kimono style reversible coat.
