Composition is a very important part of a film's mise en scène. Composition is the “visual arrangement of the objects, actors, and space within the frame” (Prammaggiore & Wallis, 82). The term “composition” literally means “to put together,” and usually arranging things aesthetically according to the principles of art. The typical principles of art are dynamism (movement), harmony (unity), variety (alternation), balance, contrast, proportion, rhythm (pattern). In the medium of film these principles manifest in the following elements:
Balance & Symmetry
“A balanced composition has an equitable distribution of bright and dark areas, striking colours, objects and / or figures” (Prammaggiore & Wallis, 82).
Lines & Diagonals
“The human eye tends to respond to diagonal lines, vertical lines, and horizontal lines in decreasing emphasis. All three may be used as compositional elements, but a diagonal line carries the most visual weight” (Prammaggiore & Wallis, 83).
An example of tight framing from Shakespeare in Love, suggesting a private (secret) exchange of words between the characters.
Framing refers to the amount of open space between the figures (actors) and objects and the border of the shot. “Loose framing refers to shots in which figures have a great deal of open space around them—this may suggest freedom or isolation, depending upon the narrative context and other elements in the frame. Tight framing describes an image in which the lack of space around the subject contributes to a sense of constriction” (Prammaggiore & Wallis, 84).
Foreground & Background
Foreground refers to the objects or action that happens closest to the cameral; conversely, the background is the part of the frame furthest away from the camera. The camera focus on either the foreground or the background with different effects.
Light & Dark
“Arranging light and dark areas in the frame is an important aspect of composition and can contribute to balance” (Prammaggiore & Wallis, 86).”
Different colours can create different moods or meanings in a film. “Because viewers perceive reds, yellows, and oranges as warm (vibrant with energy), and blues and greens as cool (relaxing rather than exciting), filmmakers choose to incorporate colors into sets, costumes, and propos according to the effect they are seeking to create. Like any other visual technique, color in the mise en scène may function as a motif.”
Colours can be described according to their saturation—referring to the strength of the colour. If the colour is not very pure, if it looks pale or washed out, it is desaturated. Saturated colours could suggest energy and vibrancy, while desaturated scenes may suggest a downbeat atmosphere. It is important to take the symbolic / cultural value of colour into account. For instance black is often symbolically used for death or mourning, and white for purity or innocence. Filmmakers may attached their own meanings to colour which you may need to decipher from the context.
Two other ways that a cinematographer may set up a frame is by using focussing on the Golden Ration and the Rule of Thirds. These "rules" are often used in art and recieves great emphasis in photography. You can learn more about them from other good websites or good books on photography or design.