"I saw this picture and started doing it but then decided I didn't like it and had to start from scratch. In the end I did this modern, edgy hairstyle where half the hair was pinned back while the other half fell over the model's face with heaps of curls set in place," Ms Nathan said.
The students said they were not expecting to be finalists, let alone the only finalists.
"At first I didn't believe the tutor when she told us, but now we think it's pretty cool and exciting," Ms Gerrard said.
Senior hairdressing tutor Sharlene Taylor said it was Waiariki's first time entering the competition.
"It's definitely set a new standard for us. I was so excited when I found out - especially given that I knew how big this competition is."
Ms Taylor said the competition would do wonders for the students' employability.
"To be able to say they were finalists in this national competition - with one who will be able to say she won - will be great for their CVs."
She said the three students displayed strong, creative skills and were able to execute their ideas with little help.
The winner will be announced on November 13.