Just ask Google to talk Headspace by saying “Hey Google, talk to Headspace”, then follow instructions. Some users may be asked to turn on your Personal Results. Here are some instructions for that.
You’ll have access to daily meditations and a sleep single. If you link your Headspace account to Google Assistant, you’ll also be able to enjoy our Basics course for free. If you’re a Headspace subscriber, once you connect your account, you’ll be able to continue your practice just like you do in the Headspace app.
Don’t have a Headspace account? You can sign up for one at www.headspace.com
Please note that Headspace does not work on Apple's Homepod.