Any form of communication some materials or ideas must be stressed more than others. Contrast can be achieved by size, shape, tone, texture and direction. Sudden change in direction give emphasis and will create contrast.
Balance
Balance is fundamental law in nature. Balance is a matter of weight distribution. Balance exist when the elements are placed with the sense of equipoise or counter balance. That is the weight of the elements counteract so that they seem settled where they placed. The weight of an element is the result of size, shape and tone. Large elements look heavier than smaller elements. In case of tone if the smaller element is heavy it looks heavier than the large elements. Irregular shapes bear greater weight than regular. There are two kind of balance; symmetrical and asymmetrical.
Proportion
When you put two or more elements together you get proportion. Whether you want it or not. This is larger than that, that is darker than this; that texture is smoother than this; and so on. Proportion helps develop order and creates a pleasing impression. It is related to balance but it is concerned primarily with the division of the space.
Rhythm
Rhythm is achieved through the orderly repetition of any element; line, shape, tone, texture. The eyes will spot the rhythm and follow it's pattern. Rhythm is the vital force in movement.
Harmony
Harmony exists in the manual characteristics of the elements: tone, shape, size and texture. A book page printed in one face with variation in sizes is a good example. Complete harmony is passive and also monotonous. Contrast on the other had is active. It gives dynamic movement and brakes harmony.
Movement
While reading our eye always moves. The eye moves naturally from big elements to little elements. From black to lighter elements. From color to non-color, from unusual shape to usual shape. Bearing this in mind the designer can start the eye travel in the design anywhere.
1. The eye moves to the left and upward after initial fixation.
2. From this point to in a clockwise direction.
3. The eye prefers horizontal movements.
Unity
The individual elements of the design must relate to each other to the total design. Without this unity no design can register overall impression.