We are located on the university campus. If you get lost in Paderborn you should ask for that. Best place to start is the Hauptbahnhof (main station). Then take line 4 towards "Dahl" or line 9 towards "Kaukenberg" and leave the bus at exit "Uni/Südring". The bus is leaving at the main station at the side of the main station. You find the exact schedule and fare information at the pages of the PaderSprinter (German only).
From there you have walk of approximated 10 min. Follow the pedestrian right hand downhill towards a short tunnel. At the end of the tunnel turn left on "Fanny-Nahtan-Straße" and follow the street passing building "L", underpass building "N" and reach building "O". Here is a map of the campus.