FFXII - Walkthrough - Ozmone Plain
In Ozmone Plain, do the following:
Field of Fallen Wings: go South to next area.
The Switchback: next area is to the southeast (there's several exits here, including one to the Zertinan Caverns, so watch out)
Haulo Green: go south, and when you can't go south anymore, go west. You'll be at Jahara!