Answer:
The six essential elements are as follows:
The World in Spatial Terms: How are things spaced out, why are they spaced out that way
Places & Regions: Specific areas and what defines them.
Physical Systems: Physical Geography(mountains, rivers, etc)
Human Systems: Populations and how they interact (cultures, religions, economic activities, migration and their movements)
Environment and Society: I don't think this one needs an explanation
The Uses of Geography: Just as the name of this implies it's how geography is used.