The easiest way to start using Fabric React is to create a web part from the Yeoman template using React and then run the following command on Command Prompt while in the web part folder:
npm --save install office-ui-fabric-react
Next, in the file you will use a Fabric React component. Add the following import statement:
import { ColorPicker } from 'office-ui-fabric-react/lib/ColorPicker';
To add the Fabric React component inside your component, use the following pattern:
You should be able to see the Fabric React component in your web part. The component has all the Office UI Fabric styling applied automatically. You can take a look at the page source to see what was actually generated: