A brand system earns its keep the day someone who has never met you has to make a decision with it. That is the test, and most guidelines fail it.
Answer questions, do not describe intentions
“Our brand is confident and human” tells a designer nothing. “Headlines are set in Funnel Display Medium, never lighter than 32px, never centred” tells them everything. Write the second kind.
Show the failure cases
The most-used page in any guideline we have written is the one showing what breaks. Logo on a busy photograph, type at small sizes, the palette in one ink. People copy the examples they are given, so give them the hard ones.
Keep it short enough to finish
Twelve pages that get read beat ninety that get skimmed. Everything else belongs in the asset library, not the document.
