Originally Posted by PunkChic
Bleach your hair with 9% hydrogen peroxide.
Remember to first apply to midlengths (most resistant), ends (which is porous so processes quick) then scalp in the end (because the heat from the scalp processes quicker).
When bleaching the hair, it goes through different stages. So when you have bleach on, it first strips out the red, then goes to an orangey colour. When it comes to put this point; DO NOT BE ALARMED. Leave the bleach on so it can strip out the orange, then it goes to dark blonde, then blonde, after that light blonde and finally white. So rinse off the bleach when you have reached the desired colour.
TIP - Keep a damp piece of cotton wool next to you so you can take off the bleach from different parts of the hair to see if it needs more time to process or if it's reached the desired result.
After you have rinsed off the bleach, you can either use a violet toner to neutralise unwanted yellow tones or you could re-colour the hair to the desired blonde shade.
As you said earlier you've dyed your hair a fair few times, when dyeing hair, the colour just builds on top of each other so the bleach may not lift out all the colours. So you might need to bleach your hair after again if your hair is up to it that is, as bleaching the hair can be very damaging!!
Another option is you can go to a college and get your hair colour stripped. At colleges they give discounted prices and are very affordable. Yes, it will be students doing your hair but then if they weren't upto the job, their tutors would not allow them to do anyones hair.