Principles of design

The principles of design govern the relationships of the elements used and organize the composition as a whole. Successful design incorporates the use of the principles and elements to serve the designer's purpose and visual goals. There are no rules for their use. The designer's purpose and intent drives the decisions made to achieve harmony between the elements.
The principles of design consist of:
Harmony
Harmony is achieved through the sensitive balance of variety and unity. Color harmony may be achieved using complementary or analogous colors. Harmony in design is similarity of components or objects looking like these belong together. Harmony may be visually pleasing and harmony is when some of the objects like drapes and couches share a common trait. A common trait between objects could be: color(s), shape(s), texture, pattern(s), material, theme, style, size, or functionality.
Contrast
Contrast is the occurrence of differing elements, such as color, value, size, etc. It creates interest and pulls the attention toward the focal point.
Repetition (rhythm, pattern)
The recurrence of elements within a piece: colors, lines, shapes, values, etc. Any element that occurs is generally echoed, often with some variation to maintain interest. Rhythm in interior design also may be used to reduce randomness.
Variety (alternation)
The use of dissimilar elements, which creates interest and uniqueness. Variety like a painting or some reflective wood panels added on a plain wall may be used to reduce monotony. Helps infuse color to a house decor to attempt to increase design beauty.
Emphasis (dominance or focal point)
Emphasis refers to areas of interest that guides the eye into and out of the image through the use of sequence of various levels of focal points, primary focal point, secondary, tertiary, etc. Emphasis hierarchy may give direction and organization to a design, and avoid subconscious confusion to sometimes improve the design's visual appeal and style. Emphasis hierarchy or focus is not giving each object in a project equal dominance within a piece of work. Emphasis or dominance of an object can be increased by making the object larger, more sophisticated, more ornate, by placing it in the foreground, or standout visually more than other objects in a project. The primary focus point or area receives the largest emphasis in a room.
Proportion (scale)
Proportion involves the relationship of size between objects. Proportion is also relative sizes of surface areas of different colors. Proportion also depends on functionality of object. Art painting can be given the correct size in relation to room to make it an effective decorating component or source of color.
Functionality
A design must have good functionality. Proper functionality is simply the best possible design and best possible location of this design that the occupant(s) requires. Such designs are clean, nearly sterile, tidy, brightly lit, warm, visually appealing, is relatively dry, has relatively clean and healthy breathing air, and exceeds high level health and safety standards. Great functionality and best possible materials for the function usually also increases visual appeal.
Proximity
Proximity is the placing of similar objects closer together physically, and unlike objects further apart. This aids in creating unity. For example, different furniture styles with different colors compressed in a small bedroom does not look as nice as the same furniture placed further apart in a very large living room.

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