I've used Sun-In on my dirty blonde hair and it turns out really good.
But since you have dark hair...I'm not so sure. My bottle of it says its reccommended for light brown hair or lighter. It doesn't damage your hair at all. It actually leaves your hair silky and soft.
The bottle says to spray it all over when your hair is damp. Then after it drys, go out in the sun for the day. Then you repeat that process the next day too. (it has to be 2 days or it won't work.)
And take note that Sun-In is permanent!!!! It's just like hair dye. Since your not allowed to dye your hair...it would suck if you used Sun-In, and got a weird color, and wouldn't be allowed to dye over it.
So it's your decision. I'm sure it'll work fine...it's just a little risky.
But since you have dark hair...I'm not so sure. My bottle of it says its reccommended for light brown hair or lighter. It doesn't damage your hair at all. It actually leaves your hair silky and soft.
The bottle says to spray it all over when your hair is damp. Then after it drys, go out in the sun for the day. Then you repeat that process the next day too. (it has to be 2 days or it won't work.)
And take note that Sun-In is permanent!!!! It's just like hair dye. Since your not allowed to dye your hair...it would suck if you used Sun-In, and got a weird color, and wouldn't be allowed to dye over it.
So it's your decision. I'm sure it'll work fine...it's just a little risky.