update readme

.changeset/neat-mirrors-wash.md

@@ -0,0 +1,5 @@
+---
+'@guardian/source': patch
+---
+
+Improve README

libs/@guardian/source/README.md

@@ -1,6 +1,6 @@
 # `@guardian/source`
 
-<img src="assets/logo.png" height="320" width="620" >
+<img src="https://github.com/guardian/csnx/blob/main/libs/@guardian/source/assets/logo.png?raw=true" height="320" width="620" >
 
 > An NPM package containing design foundations and robust, accessible React components from the Guardian's
 > [Source Design System](https://theguardian.design).
@@ -29,9 +29,25 @@ $ npm install @guardian/source
 > [!NOTE]
 > Use of the React components will require [@emotion/react](https://emotion.sh/docs/introduction#react)
 
-## Documentation
+## Usage
 
-Full documentation is available in the [Source storybook](https://guardian.github.io/storybooks).
+_Full documentation is available in the [Source storybook](https://guardian.github.ixo/storybooks)._
+
+### `foundations`
+
+Source design foundations (e.g. colour, spacing, typography etc) can be imported from the `foundations` subpath:
+
+```js
+import { palette } from '@guardian/source/foundations`
+```
+
+### `react-components`
+
+A set of robust, accessible, React components can be imported from the `react-components` subpath:
+
+```js
+import { Button } from '@guardian/source/react-components`
+```
 
 ## Contributing