A note about my process:
Mine is a 'direct' approach. The paint is applied with a paint knife, and if I am painting en plein air I begin by making a few marks with my knife to note the location of the horizon, the sky/treeline, the major lines of actions or rhythm, and sometimes the shadows. Usually the sky is finished first, since that is what may change the quickest. If there is water, I will make color notes in that area of the canvas. I will finish in one setting if at all possible, or leave the bottom corners to finish later. Glazes will be used if I feel something is wrong with colors after the painting is finished, for both plein air and studio paintings.
In the studio, I have several approaches. If there is architecture or complicated structure to the image, I will draw in major lines. Otherswise, I make line notes in paint just like my plein air work. Depending on the size of the canvas, I may need ot plan where I will stop and start, so I can avoid seam lines in my paint (much like the way a fresco painter needed to plan how the plaster would dry). I may begin at the upper left-hand corner and work down, or along the horizon and work up, or along the treeline.
Unlike most painters, I do not have a standard palette from which I never stray. There are some pigments I almost always use, but I anayze each scene to see if there are any special colors, or unique blends that I feel are required, or some that are not. That being said, I almost always use cobalt and manganese blue, lemon and cadmium light, naples yellow, permanent rose/alizarin crimson, terre verte and viridian green. I like to have some ultramarine blue and burnt umber to make a blackish grey, but viridian, ultramarine blue, and alizarin crimson will give me a great black.