In these practice sketches, I tried several different techniques. First, I only partially removed the liquid mask. This resulted in a stippling effect in some of the clouds.  I also laid down a second blue wash on the sky. I tried different ways of sculpting the clouds with gray and black pigments.

Cloud Practice 3a: With Blue Skies 030719
Watercolor Sketch
6″x4.5″ 140# Cold Pressed Watercolor Paper

In the second sketch, below, I used a darker blue as a second wash. I laid down a small landscape at the bottom of the sketch, for scale.

Cloud Practice 3b: With Blue Skies
Watercolor Sketch
6″x4.5″ 140# Cold Pressed Watercolor Paper

Here is the reference photo:

For Cloud Practice: With Blue Skies
Photo