Current light auburn hair with dark brown roots coming in. I’m preparing to do them now as always w 30 vol and ‘light red blonde’ perm color. I’d like overall color to be a bit lighter now. How long on the roots? And when do I pull it through? I know color adds color and the 30 vol needs time on my current light hair to work without darkening. I’m doing this in 10 min! Pls help!