I made a wood (cherry) brush stand, and matching desktop palette.

I used the 3 primaries, mixed for green (blue plus yellow) and orange (red plus yellow).

Direct color mixing means to mix the colors on the palette and paint the result right (directly) on the substrate.

Indirect would be putting down a glaze of one color, let it dry and layering another color over it. Since watercolor are translucent the two (or more) color mix as light passing through, bounces off the paper and reaches the viewers eye.

Decent practice exercise, right off the Corn Flakes box 🙂