I love the look of depth from layered backgrounds. When trying this technique, you must use transparent versus opaque paints. How do you know if a paint is transparent or opaque? Several paint brands, such as Golden, make it easy to see how transparent their paints are. On their label, they have a brush stroke of paint coated over black lines. If you can see the black lines through the paint, the color is transparent. If it’s hard to see the black lines, that paint is opaque and you won’t see any layers underneath. Learning about the black lines was an “A-ha” moment for me. Very handy to know.
This orange paint is transparent as you can see the black lines through the paint stroke on the label.
The blue pain is opaque because it's hard to see the black lines on the label. You don't want to use this paint to build layers as you won't be able to see any layers peeking through. Your background will turn into one color only - blue.
I created the background above by using a circle stencil. I paired the stencil with different opaque paints (orange, red and yellow). I built up layers by stenciling on top of previous layers.