To sign in and start using YouTube TV, follow these steps:

1. Visit YouTube TV: Open your web browser and go to tv.youtube tv/start sign in. This link will take you directly to the YouTube TV sign-in page.

2. Sign In with Google Account: You need a Google account to access YouTube TV. If you already have a Google account, enter your email address and password in the provided fields on the sign-in page.

3. Select or Confirm Your Profile: If you have multiple Google accounts, choose the one you want to use with YouTube TV. Make sure it's the account where you have subscribed to YouTube TV or where you want to start your trial.

4. Navigate Through Setup (if necessary): Depending on whether this is your first time signing in or if you need to set up preferences, follow any on-screen prompts to set up your account. This may include selecting your local channels based on your location or setting up your DVR preferences.

5. Start Watching: After signing in successfully, you'll be redirected to the tv.youtube tv/Start interface. You can start exploring live TV channels, accessing your DVR recordings, and browsing on-demand content.

6. Customize Your Experience: YouTube TV allows you to personalize your channel lineup, add favorite shows to your library for easy access, and explore additional features like sports packages or premium channels (e.g., HBO, Showtime).

7. Manage Settings: Navigate to the settings menu to adjust video quality preferences, enable parental controls, and manage other account settings according to your preferences.

8. Get Help: If you encounter any issues during sign-in or while using YouTube TV, visit the YouTube TV Help Center for troubleshooting tips and FAQs. You can also contact customer support for further assistance.

By following these steps, you should be able to sign in to YouTube TV and start enjoying its live TV streaming, DVR features, and on-demand content on your preferred device.