We are all encouraged to define our mission, vision and values into 3 separate statements. But, that brings its first problem - there are 3 similar but different statements - which one do you use where?
A brand (or corporate) manifesto gives you the opportunity to share just one clear statement of intent with your employees, shareholders, suppliers and customers. Yes, it's a bit longer than the 3 statement version but it does allow you to include more detail.
The brand manifesto details the guiding principles that you stand by and the goals that you have when conducting out business customer.
There is no set structure for a manifesto but it should have gravitas and real meaning and be something that people can 'sign-up to'. above all keep it short.