Head over to www.youate.com/coach/dashboard/ to create an account with a username and password. In case you have been playing around with the Ate app previously, you can use that same username and password to login into the coaching portal.
However, if the account that you created is with your AppleID, Facebook, or Google, please go back into Ate, and within settings in Ate, scroll down to "Login Settings" and Link my Email as at this time you will need an email and password to login to Ate Coach.
If you first signed up for Ate and selected a subscription, and then decided to sign up for Ate Coach and chose a subscription there as well, when you have created an Ate Coach account for yourself you automatically have access to the Ate app (when using the same email and password). In this case, please go back to the App Store or Play Store and cancel your Ate subscription as that will not be necessary to have when you have an Ate Coach subscription.