If you travel by train, you should arrive at Hauptbahnhof or Ostbahnhof.
Take S-Bahn S9 towards Pankow.
With sunny weather and if you wish to walk a bit, leave at Ostkreuz and follow the directions from google maps, stopping first at Amitola (from Ostkreuz to Amitola to Apartments Am Boxi).
With bad weather, take also S9 towards Pankow, but leave at Frankfurter Allee, take underground U5 towards Alexanderplatz, leave at Samariterstrasse and follow the directions to the apartment.
Take the airport bus to Berlin Hauptbahnhof and follow the instructions listed in "Arrival by train".
If you arrive by car, be aware that you need a permission for circulating in the Environmental Zone. You will find all the necessary information on the site Information About the Environmental Zone