You will need a ticket for Berlin zones “ABC”, available at the automatic machines at the station. You should stamp the tickets in the red boxes by the entry to the platform. Coming from the airport, follow the covered walkway to the train station. Take either the Airport Express train “RE 7” in the direction “Dessau” or “RB 14” in the direction “Nauen”, or take the S Bahn “S9” in the direction of “Spandau”. Change at the station “Alexanderplatz” onto the underground line “U2” in the direction “Pankow”. Alight at station “Senefelder Platz” (2 stops). From there it is about 100 metres to RENAC, Schönhauser Allee 10-11.