I want to preface this by saying that to get the best bright colors, you actually need to have light hair. No exceptions. If you see a brunette with pastel hair, don't get it twisted — she had someone bleach her hair to achieve that look. That said, you can definitely color your hair bright hues as a brunette, but think about layering a lighter shade, like white, under a color to make it pop. It might take more work, but you can still do it.
Now that that's out of the way, MERMAID HAIR! UNICORN HAIR! RAINBOW BRIGHT HAIR! Whatever you want to call it, it's a fun, vibrant look that lets you embrace your inner artist. And although I mentioned that bleach is involved, you can try these methods on your hair if you've already lifted to a blond tone. Check out the three methods you can DIY in the video, and don't worry — these are all temporary, so they'll wash out immediately or over a few weeks. Just remember to wear gloves and something you don't mind getting dirty, and avoid wearing white if you're using chalk!
Hair direction by hair artist Caroline Guiney.