Color notes
I learned to mix colors by trying to match little swatches to things around me: leaves, rocks, shirts, book covers. It's a calm and meditative practice built on noticing, which is a core ability for both mixing color and living a life.
So, here's something to try. Grab some paints, strips of paper and some stuff – books, mail, stickers, photographs, objects, or whatever you have at hand – and start noticing and mixing, noticing and mixing.