To activate HBO Max on your Apple TV, start by downloading the HBO Max app from the App Store. Open the app and select "Sign In." You will see an activation code on your screen. Using a web browser, visit hbomax.com/tvsignin and enter the provided code. Sign in with your HBO Max account credentials or create a new account if you don’t have one. After successfully signing in, your Apple TV will refresh, and you'll have access to all the content available on HBO Max. Enjoy your streaming experience!