How long to wait before re-bleaching hair?

i just bleached streaks into my dark hair with 40 vol. bleach 4 90 minutes and used toner 30 min. but its only yellow and i want it blonde. so can i just use 40 volume bleach again, but 4 a shorter period of time or do i need 2 use 20 volume? and also how long should i wait b4 rebleaching it? and i hav a 3rd Q = ] i know wen u dye your hair u cant shampoo for 24 hrs. is it the same wen bleaching? or does it not matter? thanx : ) [and plz dont tell me to get it lightened at a salon]

How long to wait before re-bleaching hair?
It really depends on the strength of your hair! Do a stress test ...When it's wet can you pull on about 4 strands and it stretches? If it does then you still have elasticity in your hair...if it is gummy or breaks then DO NOT REBLEACH!! You can also do a test strand and cut a piece of the bleached hair (in an inconspicuous place) and bleach it for no longer than 15 min with 20 vol and see how the hair reacts. If the above stress test turns out well then you might be fine. Otherwise you need to deep condition the hair for a week before attempting to rebleach. Also you would need to be sure someone is helping you put the bleach on the same strands otherwise you will get ORANGE streaks mixed in because the 20 vol won't lift the dark hair to even a yellow tone. Use caution! Good luck!!
Reply:U should wait at least 6 weeks.
Reply:wait about 3-5 days so your hair isn't so weak that it falls out





i've bleached my whole head of hair many times
Reply:It really depends on yrr hair. to be safe I'd use 20 volume and not shower for 24 hours