A useful guide starts with a brief description of the audience, positioning, and message the brand should convey. It should then show approved logo versions, colour values, typefaces, imagery direction, and examples of how those elements work together. Add voice and tone guidance with sample headlines or customer replies. Clear examples of what to do and avoid are more helpful to a busy team than a long list of abstract adjectives.
Make the guide practical for the people who will use it. Include templates or examples for your most common touchpoints, a link to approved files, and the name of the person who can answer questions or approve exceptions. Review it when your offer or channels change. REX’s Brand Foundation page outlines the kinds of visual and marketing assets these rules may need to cover.