Contrast-The Presentation of two elements of the design in opposite ways
Alignment-Placing text and other design elements on a page so that they line up
Repetition-The use of same and or similar elements in your design
Proximity- The process of ensuring related design elements are placed together
Proportion-The relationship between of two or more elements in a composition and how they compare to one another with respect to size, color, quantity,etc.
Emphasis- is defined as an area or object within the artwork that draws attention and becomes a focal point
Formal Balance- means the elements in the design are symmetrical
informal Balance- means they are not strictly symmetrical, but look to be so because of the composition of slightly asymmetrical elements
Unity- to make elements in a composition appear to belong together
Variety- is about varying elements and objects in your image.
Camron Blog 