By car:
From the north and the west: You can reach Gosau from the Salzburg freeway A1. The you continue driving on the Tauernautobahn freeway A10 till Golling and further past Abtenau, Russbach past the Pass Gschüt, 957 above sea level, until you get to Gosau. It will take you about an hour to get from Salzburg to Gosau.
From the east: You will take the A1 freeway to Regau, then past Gmunden, Bad Ischl and Bad Goisern.
The time for travelling which you have to calculate from Linz to Gosau will amount an estimated 2 hours (1 hour to Gmunden).
From the south: You get on the Tauernautobahn freeway till Golling, further past Abtenau and Russbach until you reach the Pass Gschütt, 957 above the sea level. It leads you directly to Gosau.