Going back to natural from dyed blonde

I've been dying my light brown/dirty blonde hair blonde since I was 13, and I've gone brown a couple of times in the hopes of growing my natural color out. I never went through with it, BUT i do know alot about how your hair might take it lOl.

First, make absolutely without a doubt sure that you will not want blonde hair back next week, because i've done the transition BACK to blonde, and to put it simply, your hair will be wrecked. for a longg time.

Anyways, if it IS what you want, I would suggest doing a single process color over your entire head thats as close to, or even slightly darker, than your natural color. If it's slightly darker, when your roots grow in, they will blend alot better and you will eventually have your natural highlights blending in. also, dark hair dye layered onto blonde hair WILL fade with everyday wear and use, so a shade or two darker will wash out and lighten up a bit.

I wouldn't do lowlights, because that plus the light ash blonde PLUS your darker roots growing in will just look a little messy.

I like the L'Oreal line of haircolor for at-home, and I've discovered that if you can't find the exact color you want, mixing two is alright sometimes -- you have to make sure the undertones match though! no mixing a "golden so and so" with a frosted, ash, or "light so and so" -- your hair will turn a terrible color. Sally's beauty supply has slightly higher quality L'Oreal haircolor that has very accurate color samples, and mixing is more foolproof. Also, after you wash it, BE CAREFUL with what color shampoo and conditioner you use in the ensuing days! I used a purple one once, and lo and behold my hair had an interesting  sickly purple-gray tint to it afterwards.

I don't know if any of that helped, hopefully it did! good luck!