Okay, so that's it! You should now be well on your way to becoming a world-class developer. This book is intended to lay a foundation for you to get started and get a better idea on how to improve the speed of your responsive website. There is so much more that can be said about responsive design—some things were not even covered.
You should take the knowledge you gained, proceed with it, and add your own flavor. Read about what other people are doing to improve their websites and bring it all together.