With celebrities such as Demi Lovato, Ke$ha and Katy Perry swapping their natural colours for something more daring too, why not follow suit?
Holly has teamed up with hair dye company Manic Panic and, while some celebs spend hours getting top stylists to preen their tresses, she colours her locks herself at home - for a total cost of £22!
The Newcastle-born star tells Reveal: "I dye my hair myself at home every three weeks or so, it depends how often I wash it.
"Being bright, the colour can fade quite quickly, which is the only downside. I love dying my hair myself - I'm no diva!"
Holly uses Manic Panic's semi-permanent Electric Amethyst, £11, on her roots, then she mixes this colour with Manic Panic's pink Cotton Candy, also £11, on the ends for an ombre look.
Before switching up her style to purple, Holly used the range's Rock 'N' Roll Red, also £11 for a semi-permanent tub.
If you're not brave enough to sport a bright colour for several weeks and would prefer something a little more temporary, fear not!
Kevin Murphy's wipe on wipe off Colour Bug comes in five different colours. A tub costs £13.95 and you can colour your hair just for one night if you want.
Beauty brand Sally's Crazy Colour in Hot Purple, £6.49, also washes out easily, while Fudge's Paintbox in Blueberry Hill, £9.25, lasts from three to 30 washes depending on your natural colour.
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