How do I bring my hair back to blond if i died it dark brown?

Hey well ive been there and your hair is gonna end up like mine. its now dead, blondish whitish and dry as. I went to the hairdressers each 3 months. they told me the best thing is to use bleach and something else. my hair was dark brown - then red - then orange - then dark blonde - then blonde. then i used my own toner at home. Consult your hairdresser first and remember to use treatments all the time whilst your hair is being processed,. use moisturisers and anything u can find. PS. AVOID STRAIGTENING IT. I DO AND MY HAIR IS DEAD LOL. OH WELL. :(