Design principals from:
Williams, R. (2008). The non-designers design book. Berkeley, CA: Peachpit Press.
Similar design elements should be avoided. Elements should either be the SAME or VERY DIFFERENT.
Image Source: makesigns.com
Repeat elements throughout the design in order to create a more unified piece.
Text and images in the design must have a visual connection to other text and images. No element should be placed arbitrarily in the design.
Image Source: Lesa Snider, Macworld
Related text and objects should be grouped together.
Image Source: VWO Blog Design Principles