When selecting the photo, or when deciding to pose for the photo that will be used for the portrait, the tenets of good photography portraits pertain to the oil portrait. I found a photographer who blogs about his work, and he always recommends that clients choose clothing with solid colors, or at least prints with low contrast, i.e., nothing too loud or busy. Avoid plaid, stripes, logos, or trendy styles. Similarly, avoid big or shiny jewelry or belt buckles. Go for neutral or muted colors because bright, flashy colors will draw attention away from the smiles and the people.
Portraits turn out best when all the colors fall in the same tone range. In other words, you should be able to identify a pleasing color scheme. Think of the way a bride or wedding planner arranges the colors of dresses, flowers, etc. You don’t need to match colors exactly, but consider that if you include more than one shade of a single color (for example, faded vs. bright blue), it may look like you tried to match but failed. Even modern era portraitists, who used stylized textures and lines, usually relied on solid colored clothing to make pleasing compositions. Tamara de Lempicka, a painter in Paris in the 1930s, chose a white satin gown and a red coat for her Portrait de Madame Boucard. In another, Femme au Col de Fourrure, Lempicka decided that her subject wear a teal dress with a brown coat and white gloves.
Let’s talk about how setting, clothing, and theme can all work together to 
make a successful portrait. In the previous examples, women were depicted in coats. For your own portrait, if coats were the clothing of choice, it would seem natural to have an outdoor or even a snowy background. If the subject(s) wore casual summertime clothing, perhaps a sunny green backyard or a blue sky with beach would help tie the composition together. These choices help communicate the personality of the subject(s). If it is a portrait of 2 more people, no one person should wear anything extraordinary compared to the others.
Because oil paintings are well suited for portraying a certain elegant realism, this may be the approach you decide to take when making your theme and color choices. A formal, or classical, approach to your portrait may mean that the poses are more rigid, the perspective is the most flattering possible (but not necessarily the most natural), the setting shows off luxurious items like velvet curtains or gilt-edged books, and the clothing is expensive and freshly dry cleaned. However, many contemporary oil portrait clients prefer a more natural and unassuming style of portrait, as with the aforementioned beach background portrait. Given that the outdoor setting is rather informal, it may fit best with informal poses and clothing. An informal pose is one that looks very comfortable and typical for the person, and in which perhaps one or more subjects do not face the camera.
Author: Julie Ann