How to go from bright red hair to dark ash/pearl blonde hair?

You are in for a world of trouble if you do it yourself... b/c for one you are trying to go from a red base to basically a blue/green base color. Which means a lot of bleaching to take the red out... And then you will need to use a blue or green base toner that is blond on your hair...without experience in doing this I say go get it done.