A principle for having quality visuals is​

A) Dark colors appear nearer;light colors appear further away​
B) Avoid using colors that end to look the same at a distance.
C) Place opposites on the color wheel immediately next to each other.
D) ​Use light colors for bullets or letters on a clear background. 

Visual Aids

Objects, models, graphs, charts, and images used to enhance comprehension and retention of information during presentations.

Dark Colors

Colors with low lightness or brightness, often associated with depth, sophistication, or somberness.

Light Colors

Refers to hues that have a high value and low saturation, often perceived as soft, soothing, or pastel.