If create-react-app, craft and yarn are not installed yet:
$ npm install -g create-react-app craftool yarn
To create your BAREBONES create-react-app app:
$ craft your-app-name-here https://github.com/react-u/create-react-barebones/archive/master.zip
To work on your app now do:
cd your-app-name-here
yarn && yarn start