I am in the process of making a video of my color spots of value approach. In the meantime check out what I have learned so far.
Break your thinking up into darks and lights. I find the NOTAN method is fool proof for this. I outline this in my book Three Step Watercolors. It is the foundation piece upon which everything else gets established.
What I have learned so far:
Establish what is in light and what is in shadow . Then follow the rule that nothing and I mean nothing not even a white spot of local color can be as bright in the shadow as the darkest light local spot is in the light .
This is super key. Local color ...the color something is in real life can not "trump" ( sorry) the rule of light and shadow.
I am a watercolor coach, watercolorist, and author.