Select your app.
Click "TestFlight" at the top.

Click "Create Group" to create a new group of internal users that can test your app.

Enter a name for your tester group, e.g. "My Testers" and click "Create".

Click the plus button to add a new tester.

You can now select testers from all the users that are members of your developer account. In most cases, unless you've previously added more users, you will only see your own account and our webtoapp.design account.

Click the "Add" button.

The selected testers will now receive an e-mail with an invitation link. They need to open the link, which will then show an invitation code.

Afterwards, they should download the TestFlight app from the App Store on their iPhone or iPad where they wish to test the app.
Inside the TestFlight app they can now click their profile picture to bring up the settings screen.

On the settings screen, the testers can click "Redeem" and use the invitation code from the website to get access to the app and install it on their device.

