I've recently started dying my hair. I use L'Oreal Castings. I assume all hair dyes have similar instructions, but you're meant to squeeze the tube of colour into a bottle of reactive agent(?).
The think is, I have very short hair (less than 2") and I reckon I could easily get away with using only half.
Could I just mix half the tube with half the bottle in a bowl, rather than shaking the whole lot together? Would the remaining unmixed ingredients keep until my next hair-dying session?
Thanks