hi all, seeking some advice as it has been a while since I last did a big colour change, it happens to be on my friend, who normally has full head foils bleach blonde, she has now decided she wants to go darker, she has a natural base of 5, obviously im going to have to pre colour, so thinking dia light 6.3 + 6vol, then just a 5 in dia richesse after? she's wanting to be dark like her natural base, this is where I'm stuck and my brain isn't working. Any advice would be amazing.