The No Doubt rocker confessed that it took time for her to discover her signature style, but said that she knew right away when she found the look that suited her best.
"I remember sitting in my ghetto, beat-up Honda Prelude, and putting on that lipstick in the rear-view mirror and being like, 'Uh-huh, I like that. That's the s**t right there'. I never stopped after that," Stefani told Harper's Bazaar.
When it came to dyeing her hair the platinum blonde colour she has become known for, the 42-year-old explained: "It was like I'd unlocked the key. I remember feeling like, 'I have arrived. This is me. Finally'."
Stefani also admitted that she wears make-up to please husband Gavin Rossdale as he likes her better in it.
She recently said that she finds the No Doubt reunion to be "exhausting" as it requires a lot of hard work and long hours.
Watch No Doubt's video for 'Settle Down' below: