The star loves to switch up her hue by using various home dye kits.
Despite her mane always looking enviably shiny no matter what shade she sports now, Olivia wasn't as savvy with changing up her locks as a teenager.
"At one point I went from blonde to brown, and that gave me green," Olivia told People. "Then I just went black. And when I tried to [go] blonde again, I was left with a black stripe around the middle of my head. It was really unattractive."
Olivia has since mastered a technique for experimenting with her appearance in a more successful manner. The actress is now a global brand ambassador for beauty brand Revlon, and has learnt to be patient with the process when trying out a new shade on her tresses.
"I change my hair colour so often for work that I get to experience all shades and all styles," Olivia continued. "I'm a big fan of experimentation, but with that it's all about doing it slowly. Luckily, my hair hasn't fallen out, which is really amazing considering how much I dye it."
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