my hair now is medium golden blonde and i want to go cooler champaign blonde. ive heard ash over gold can turn hair green. i also have a few inches of dark blonde roots and dont kno if i should do the roots first or just do all over. ive only died my hair a few times before and its usually come out ok. i tried doing blonde highlights a few months ago and they turned out orange so i did an all over medium beige blonde and it turned out nice but its starting to get brassy at the ends and i think ash would look better on me anyway. so just nervous about hair and need opinions from people who kno what there doing before i do it...
I would do the roots first. You want to use a color with a violet
base over what you have if what you have is too yellow, but your roots
will likely come out orange if you don't do them to match the rest of
your hair first. Ash can go green if the blonde dye has a green
base, but you don't want one with a green base to do the hair you
already did to yellow, you want one with a violet base. (You
won't be
able to tell the base of the dye if you are using drugstore box color,
its not written on those, you have to shop at a beauty supply
store like Sally). You will also have to test strand. You
don't
want it to go too ash or too light or do anything funky, so test
strands will help you get the timing right, and to see if you're using
the right strength of developer.