A personal interview is not uncommon even in case of internships. Since it’s simply impossible for applicants from Maghreb or Levant counties to travel to Germany for an interview, it’s important to ask in advance whether it is possible to have an interview via Skype or another video chat channel. More or less all HR officers will understand that. However, a “distance interview” is not very different from a personal one.
Appear in person (HR officers are professionals. They realize if you try to cheat them.)
Appear in time. (i.e. 20 minutes early)