Warm up with a few notan thumbnails (sketches that group the area into two to five values) breaking up the composition into a simple abstract statement.
Make sure you have an unbalanced amount of light vs. dark, use the rule of thirds, and figure out your focal point (what you want to say/where you want to guide your viewer to focus)
Refer to your chosen thumbnail throughout your painting.
Identify the temperature of your light! Paint shadows the opposing temperature.
Do NOT hold you brush like you hold a pen or pencil…this will instantly create a war between your right (creative) brain and left (logical) brain. Hold the end of your brush, and try to paint from your shoulder.
Stain/tone your canvas with washes warm bright colors. Sketch the basic outline of the major shapes—think in large puzzle pieces! Try to avoid drawing more than five basic shapes. You can break them up later.
Paint the most obvious/saturated/eye-catching color shape first. This should be the area that speaks to you the most.
Paint your darkest darks fairly thinly and transparently. Proceed painting all the dark areas you marked in your thumbnail.
Paint your lightest light thickly and opaquely. (Not pure white! Remember light has a temperature and a color.) Proceed to paint all the rest of the light areas you noted in your thumbnail.
Break up shapes making value, temperature, and saturation adjustments one puzzle piece at a time. Push, pull, scrape, and add paint as needed. This is the fun part! You can add more medium to your paint piles at this point to help them layer more easily.
Adjust edges and add detail.