The eight decisions
Colour tokens, a type scale, a spacing scale, a radius scale, elevation, motion timing, iconography and one grid. Everything else is composition.
Write them as tokens in code, not as a slide. A design system that lives only in Figma is a mood board with governance meetings.
Enforce with defaults, not documentation
Nobody reads the 40-page guideline. Make the correct choice the easiest one: a Button component with sensible variants beats a paragraph explaining when to use blue.
Lint for raw hex values. If a colour cannot be added without a token, drift stops on its own.
Version it like software
Small teams can afford a single release channel. Tag versions, write a one-line changelog and never silently change a token's meaning.