It seems like every day another celebrity is turning up with a pastel hair color. Often times this is seen with blondes since the color shows up well, but it can actually work with brunette hair as well.
The thing is that with brown hair you might have to go permanent as opposed to being able to chalk or spray in a temporary color. Of course, this means that you have to be certain about the look, but if you want it that’s the best way to get it.
One thing you should do to prep is look for colors that you want and bring them in with you to show as examples so that you don’t leave the color up to interpretation. You should also make sure and keep your hair super moisturized for a while using masks at home to prepare for the color change which might require both bleach and color.