There are many things you should think about before you create your bench ad design. First and most importantly is the coloring. Light rays have varying wave lengths and frequencies. Some pigments absorb light and others reflect it, the outcome of these frequency is then perceived as color. Primary colors together (like red and green) create vibration that makes it difficult to read.
The stronger the contrast of hue and value, the stronger the design will be. Hue is the identity of the color while the value of the color is the lightness or darkness. The strongest contrast design is yellow and black. They are dissimilar in hue and value, which makes it easy to read. Below are a list of good color combinations and poor combinations.