It's easy to link to your Google Home device. Just use these steps:

1. Download the Google Home app (iPhone/iTunes or Android)
2. Launch the Google Home app, and click the Devices icon in the upper right corner. 
3. Select Settings for the home device
4. Go to Videos and Photos settings
5. CBS will show as an option. Tap Link, then tap Link Account. CBS All Access is now linked!
6. Log in with your CBS All Access credentials
7. You can now use Google voice commands with Chromecast   

Please note: Google Home works with CBS All Access, so you'll need to be a subscriber. Only full-episode shows are supported, but movies are coming soon!