Open the Profiles page and use the blue + button to create a new Mobile Provisioning Profile.
Apple Developer Portal - Profiles list
Select the option In House and click Continue.
Apple Developer Portal - Create new Provisioning Profile
Select the App ID of your app and click Continue.
Note: You can follow the steps in this article to create an App ID for your Enterprise app.
Apple Developer Portal - Select App ID
Select the iOS Distribution Certificate that you've created and uploaded in AppMachine, and click Continue.
Note: You can find the expiration date of your iOS Distribution Certificate on the Certificates and API Keys page in AppMachine. If you haven't created an iOS Distribution Certificate yet, follow the steps in this article.
Apple Developer Portal - Select iOS Distribution Certificate
Enter a name for the Provisioning Profile and click Generate.Note: The Provisioning Profile Name is purely for your own reference and is not used outside of the Apple Developer Portal.
Apple Developer Portal - Enter Provisioning Profile Name
Download the Mobile Provisioning Profile and follow the steps in this article to link the profile to your app in AppMachine.
Apple Developer Portal - Download Mobile Provisioning Profile