Black and brown to blonde

I have the nottom half of my hair black and the top brown (its funky :D) and im bored of it now so I want to go blonde, I am worried that it will turn un healthy and im unsure as to whether it will deffinetly come out the right colour if I go to a slon to do it instead of doing it myself, will my worries happen ?

If you go from dark brown to blonde all at once, it will not only fry your hair, but it'll likely turn out orangey. What you do is gradually go blonde, by dying it no more than two shades lighter at a time. Wait a couple weeks and do it again. Keep repeating this process until you have the shade you want.

dude, I've got the same problem D: