UI Coach guide
Design System Best Practices
How to build a design system that teams actually use: tokens, components, documentation, and contribution.
By UI Coach Editorial ·
A design system is a shared language for building product UI. It is not a Figma file of pretty components. If engineers cannot implement it, if designers cannot find it, or if the only consumers are the people who made it, it is a library, not a system.
Start with decisions, not screenshots
Tokens for color, type, and space encode decisions. Components encode interaction. Documentation encodes when to use which. If you only ship screenshots, every team will invent a slightly different button.
Make the default accessible
Contrast, focus, names, and keyboard behavior should be correct in the primitive components. Product teams should not have to rediscover WCAG on every screen. GOV.UK's public design system is a useful reference because it treats accessibility as a default, not an add-on page.
Document do and don't
A component page that only shows the anatomy still leaves people guessing. Show the intended use, the invalid use, and the content rules. Vague labels leak into production if the system never says otherwise.
Plan contribution
Someone will need a variant you did not predict. Without a contribution path, they will fork. With a path that takes six months, they will also fork. A lightweight review that protects the core primitives is the usual compromise.
Common mistakes
- Building 200 components before the first four are stable.
- Design and code drifting with no source of truth.
- Treating the system as a brand police force instead of a delivery tool.
Practice this on UI Coach
Admin and design-system-flavored challenges are a place to practice primitives: buttons, inputs, tables, empty states. Pair that with design system resources and Figma plugins, then look at jobs that mention design systems. The market is asking for this skill by name.
Sources
- Nielsen Norman Group, Design Systems 101
- GOV.UK Design System