From the centre of Zürich follow the signs for Rapperswil. Stay on the road along the lake (which is now to your right) through Zollikon. 500m after the place-name sign of Küsnacht continue at the traffic light straight ahead for another 800m where you turn left into Kohlrainstrasse (this is before the second traffic light in Küsnacht).
After one street immediately to your right which you pass the Kohlrainstrasse turns after 50m itself to the right. Continue for another 100m. Just after a street to the right you will find at the right hand corner of the street Kohlrainstrasse 10, a bluish office building.
S 16 (from the airport via the city direction «Meilen») or S 6 (from the city direction «Uetikon») to station «Küsnacht» (not Küsnacht-Goldbach, which is one before). Pay attention that S 7 going to Meilen does not stop in Küsnacht.
Leave the train station at the side to the lake, turn right, after 80m in the direction back to Zurich you will find on your left Kohlrainstrasse 10, a bluish office building.
From Zürich City (e.g. Zürich Bürkliplatz) to station «Küsnacht»
Walk up through the pedestrian underpass 150m, turn left before the train station, after 100m on the left is Kohlrainstrasse 10, a bluish office building.