Avoid placing the focal point in the middle of the painting, either vertically or horizontally, except for formal compositions. Unequal distances add interest. Start with the basic shapes of your subjects, ensuring that the proportions and relationships are correct before gradually adding detail. The image may be vague or a complete roadmap of your final painting but planning at this stage will impact the success of your painting. Double check your drawing before you begin painting.
Check angles, distances and proportions.
One of the easiest and most foolproof ways to check for mistakes is to look at your drawing in a mirror. Start with an underpainting of a harmonious color which will provide a foundation and provide the atmosphere for you painting. For a landscape, an underpainting of ocher, sienna or umber will set the tonal values. Limit your palette to two or three colors at the early stages of your painting. More intense colors can be added in the later stages.