I should imagine you'd need to tone the ends after you've lifted them.
So I'd probably balayage first, process and rinse. Then do your root colour and blend it with your toner on the mid lengths and ends.
If you look at the photo I've attached you can see that the cool is much darker than the warm. The warm is brighter.
If you would be happier with say the last 2 swatches, they are more neutral. Neutral is neither warm nor cool. But will definitely be closer to what you're looking for.
I pretty much always do this anyway only because a lot of clients don't actually like their natural colour. Use a Demi if you're not having to cover more than 50% of white hair.
If your client prefers not to have a root colour. You just have to backcomb more with a teasing brush or a few ne...
I'd backcomb through the top sections from the Mids up and do slices across the top as you suggested.
Then I'd freehand through the underneath adding a few foils around the face if need be.
Other people will tackle this differently and that's okay, we're all different. As long as you and the...
Your hairdresser is correct, she cannot use anything lighter than a level 9 on a level 9 as it won't do anything.
If you want bright on a level 9 you need to have some form of warmth. Brightness comes from gold, not ash.
Ashes are much denser tones than golden / warmer tones which don't let...
Colour touch is technically better, because of the nature of it.
But if you want a good lilac then illumina 9/60 is great.
And a blue grey, would definitely recommend colour touch 20 parts 8/81 a tiny spot of 2/8 (tiny tiny pea size)
I'm not a mobile hairdresser so not sure if this would be practical.
But could you not keep tools and PPE etc in the big bag? And the other use a storage tub to put your colour tubes in bottom end first so all your shades are showing face up? Might be easier, at least that way you can take in...