You need to be a registered member, which is free of cost. Your data won´t given to any third party.
1. Move the mouse to your nickname right above, menu bar opens.
2. Left click on "Einstellungen", another page with menu bar opens.
3. Left click on "Benachrichtigungen und das Verhalten des Forums ändern", another page with menu bar "Einstellungen" opens.
4. At "Sprache", left click on the arrow beside "Deutsch" and then left click on "English".
5. Confirm with left click on "Speichern" below the box.
The forum language for you is English now.