Update readme

Author: acelaya

README.md

@@ -6,3 +6,21 @@
 [![Paypal Donate](https://img.shields.io/badge/Donate-paypal-blue.svg?style=flat-square&logo=paypal&colorA=cccccc)](https://acel.me/donate)
 
 Coding standard used by Shlink JavaScript projects.
+
+This library includes two ESLint configurations, the base one, and the react-specific one. Default export includes both:
+
+```js
+// eslint.config.js
+import shlink from '@shlinkio/eslint-config-js-coding-standard';
+
+export default shlink;
+```
+
+If the project does not use React, you can just use the base config:
+
+```js
+// eslint.config.js
+import { baseConfig } from '@shlinkio/eslint-config-js-coding-standard';
+
+export default baseConfig;
+```