What will mixing baking soda with my shampoo do for my hair? I've been trying to lighten it for weeks and cant?

I have naturally dark blond hair, I dyed it dark dark brown with a hint of purple for about six months straight and now I want blond again, I've been trying to go slowly lighter for WEEKS, I keep getting an awful red-ish blond. What can I do!?!What will mixing baking soda with my shampoo do for my hair? I've been trying to lighten it for weeks and cant?
bleech it blonde.


answer mine?


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