M missbonga New member Oct 22, 2010 #1 i accidently bought a 40 volume developer.. i want to touch up my roots but im afraid my hair will break. i always used 30volume before.. should i mix da 40 volume with 20 or can i mix it with water??
i accidently bought a 40 volume developer.. i want to touch up my roots but im afraid my hair will break. i always used 30volume before.. should i mix da 40 volume with 20 or can i mix it with water??