Keep It Simple!

You should not put more than a few words on a billboard. Why? Two reasons:

First,

you can’t grasp more than a few words and pictures while reading and driving at any speed.

Secondly,

the size of the words is very important – you want to keep the main copy at approximately 36”character height. So the fewer the words, the larger the type and the better the visibility. To make this happen, you have to distill the advertiser’s message down to its simplest form.

High Contrast

The Outdoor Advertising Association of America in 1928, published their findings of exhaustive research into what color combinations are the most legible on a billboard.

in order of success, for maximum contrast

The top 5 best colors are

When the words and background on a billboard have little contrast, it is very difficult, if not impossible, to read the message...
If you cannot read the message, the ad is less valuable.

Ask Yourself

For the best tips on developing effective artwork, read these OAAA Guidelines!

These 14 color combinations represent the best use of color contrast for advertising readability. The chart evaluates primary and secondary color combinations taking into account hue and value. Example is the most legible color combination while example 14 in the least legible.

Hue is the identity of colot, such as red, yellow or blue.
Value is the measure of lightness or darkness and can be separated into shades and tints.
Shades are the relative darkness of the colors.
Tints are the relative lightnessv of colors.