You can install the prolyfill by downloading it from GitHub or via npm. After installing you can use the container queries as described in Usage.
Download the file cq-prolyfill.min.js from the latest release on GitHub.
To install it via npm execute the following command in your project directory:
npm install --save cq-prolyfill
After the installation completes you can find the prolyfill at node_modules/cq-prolyfill/cq-prolyfill.min.js or you load it via browserify or webpack.