This painting needs a darker sky and it would really be nice, unfortunately because of the way the sky is painted it would be really complicated to darken it, not impossible but the transparency would be lost and I would rather have a nice looking sky and the feeling of light well stated than to have a really powerfully stated surf. I like the light filled quality and I guess that is the best I am going to get in this artistic trade-off. I painted the sky with a mixture of cobalt blue and ultramarine blue greyed with some burnt sienna and a little bit of cobalt violet for some warmth. Try to get some variety in the values in the sky keeping everything light but still varied, remember to leave light for the surf and paint the background water.Paint the rocks with raw sienna cobalt blue and a little cobalt violet, and the scrape some highlights off the top of the rocks. Use a vigorous brush mark at the bottom of the rocks, try not to cut them off with a hard edge, water is moving at this edge.Use a grey mixture of cobalt blue and burnt sienna for the shadow in the surf and the gray water between the rocks. Use a round brush for these areas and a damp paper towel to correct the edges. Splatter some raw sienna mixed with olive green into these areas to express sea weed or organic material being thrown along with the surf.Paint some darker accents in the water on the right and in front of the rocks, darken some areas on the rocks to help create the form of the rocks.