I worked on these 24 x 20" canvases off and on for several months. When I had a call for two paintings for someone's dining room, these were the perfect size and beginning. They are very fond of the beach, so the aquas and greens with the sandy textures reminded me of the ocean. See a slideshow below.
Starting with warm colors on one, and cool colors on the other, I just made marks. After each layer was dry, I alternated the colors. This is an excellent way to keep colors fresh and separate. If I had mixed the colors I'd have a lovely shade of brown. AND, I didn't want brown…that way.
I used spackling paste (modeling paste is the artist product) applied through a couple stencils I felt reflected my client's taste. These may have 15-20 layers, creating visual and tactile texture. Toward the end I began to see shapes, but didn't commit to any of them.
Next, I took a small electric sander and sanded them for several hours. This allowed some of the early layers to peek through. I kept things fairly neutral throughout, and let the shapes appear on their own. A few begged to be developed, and I knew I could always cover them up later.
Toward the end, I applied gold leaf in random lines to create movement, keeping them very organic (rough). I was careful to keep each canvas unique. The last layer was a thin wash of warm white in shapes that accented some of the gold lines.