Principles of Design are paramount to a good designer. Look at your surroundings and you will see all these principles applied throughout your life on a daily basis. These include:
Balance
In design, balance creates a feeling of equilibrium. It is all about equalizing or approximating the visual weight of objects. Balance is created not just through shape, but through color, pattern, and texture as well.
Rhythm
Rhythm in design is all about creating patterns of repetition and contrast to create visual interest. This can achieved by using the same color or shape at different intervals. Its purpose is to move your eye around the room.
Harmony
Harmony is created when all the elements act together to create a unified message. Just as rhythm can create excitement, harmony creates a sense of restfulness.
Emphasis
A room where everything gets equal importance will seem either scattered or boring. You need an anchor. Architectural spaces often have points of interest such as a fireplace or a window with a beautiful view.
Proportion and Scale
Proportion is the ratio between the size of one part to another, and scale is how the size of one object relates to another or to the space in which it is placed.