“We are able to hear a single tone.
But we amost never (that is, without special devices) see a single color unconnected and unrelated to other colors.
Colors present themselves in continuous flux, contantly related to changing neighbors and changing conditions.”Josef Albers, “Interaction of Color“, page 5
Stop worrying about getting one colour absolutely right and spending ages mixing it. That colour is going to look different when you put your next ‘absolutely right’ colour next to it anyway. So go with ‘more or less right’ and adjust once there are lots of colours in play. Interaction is the name of the game.