Hi, I'm a level 3 student studying in Glasgow and I was looking for some advice with the Wella Koleston colours. I have a client who usually has 66/0 to cover her greys and a 6/03 for a golden tone to her hair. Last time she had her hair coloured she wanted a bit of warmth in it, and it turned out more red than I had hoped. She wants to return to the golden tone she had before, but I don't know if applying the 66/0 and 6/03 would work over the warmth in her hair? Thanks!