Tierney started dancing from a very young age, studying ballet primarily and attending her local dance school alongside weekly associate programmes. At the age of 16, she joined the Centre for Advanced Training at The Place and Rambert’s Youth Company: Quicksilver. After two years of training she was accepted onto the degree course at Rambert School and moved to London to train full time.
During her time at school, Tierney choreographed and performed in many student pieces and worked with choreographers Monique Jonas, Julie Cunningham and Connor Scott. She was also the Conservatoire for Dance and Drama student governor during her final year.
Alongside her dance training, Tierney worked as a dance teacher for local dance schools, teaching Ballet and Contemporary classes and choreographing pieces for shows and competitions.