dying your hair would damage your hair no doubt, depends what colour u gonna get as well, from what i hear, if you bleach it, the colour will be brighter as well u can bleach your hair to be blonde, bleaching is bad for your hair though, but if you want a certain colour, you might have to.

if you dye your hair out from the box, always try to go another box up, as in another shade lighter, if you hair is black or dark brown, because colours don't usually come out like it says on the box because dark hair is hard to dye. and if you do dye it from a box, i tend to leave the hair dye longer than i am suppose to, so the colour might stay on a bit more

if you were to dye it at a salon, they charge around $50 and up, depending on the colour, and how u want it and how long your hair is? i'm not too sure, cuz i haven't gone out and did it before.

Hope that helps.