To connect YouTube TV to your Roku device, start by turning on your Roku and navigating to the home screen. Select "Streaming Channels" and search for the YouTube TV app. Download and install the app, then launch it from the home screen. Select "Sign In" and a code will appear on your TV. Using a computer or mobile device, visit tv.youtube.com/start, and enter the code displayed on your TV. Follow the on-screen instructions to complete the setup. Once linked, you can enjoy live TV, on-demand content, and DVR features seamlessly on your Roku device.