For those familiar with Android phones, Developer Mode is similar to enabling root access on your mobile device. It allows you to enable functionality not present in the standard ChromeOS settings.

Each time you turn on your Chromebook with this mode, it will automatically boot to this screen, and you will press the same button each time. Wait for the loading screen to signal completion.

Use the toggle available for the Development Mode option to turn it on. A confirmation box (Use developer features) will open. Press the Yes button in that box.