Preston Crayford was born in Wellington to film maker Gaylene Preston and musician Jonathan Crayford. Apart from appearing in a water safety commercial at the age of four, her acting debut was at the age of 13 in the New Zealand-made TV series A Twist in the Tale starring william Shatner. Several years later, her performance in a stage production was praised by Ian McKellen, encouraging her to pursue an acting career and enrol in the Toi Whakaari national drama school from 2006 to 2008.