Random mixing.

I was always cleaning up the lids of my watercolor boxes.  Seems like a tidy way to do things. Start fresh every day.   Just wipe with damp paper towel.  Done.   

BUT-  I observed friends who are better water color painters were leaving their mixing trays messy.      hmmm... whats that about.       I started to leave mine messy and discovered many interesting neutrals can be mixed with the dried colors.   Mixing one neutral with another...    what amazing colors.     I think because they are more experienced they recognize those dried colors and the mixes.  Perhaps they have a preferred palette and rely on certain colors.   
Because I am using such a variety of references -i often try to match the palette to the ref. 

I usually mix my colors on the paper wet into wet or by glazing over a dried color.    Im working my way through this puzzle.      I think i will try more of the tray mixing.       Im agaist wasting good paint.    I hated to toss those damp paper towels with the interesting colors after cleaning up.    Lol.