Not many people would do this path to reach Hohensalzburg Fortress. They normally take the easy route by walking through The Old Town.
Another way is by walking/hiking up the small forest area called Monschberg.
It's quite easy if you like walking. I was lucky to have a guide showing me this path.
Nevertheless, I am sure you won't get lost in this area if somebody is accompanying you or you do this walk during the day where you could see some joggers or walkers around this forested area.
Here I include the map for easy (I hope) guidance for any of you who want to follow this path...
Notice the 3 main points/areas :
The Train Station, walking towards the Salzach River;
The Monschberg area;
The Hohensalzberg Fortress.