Instructions
Download "Flight Simulator X" scenery-editing tools, such as SBuilder X, FSX Planner, or FSX KML. These downloads are free and easy to find with a simple search of their names.
Install the software onto your computer by opening the zipped file and extracting the contents onto the desktop. Double click the ".exe" file to begin installation or to run the program.
Select the editing tools on the FSX editing software. For example, upon selecting the "Object Placement" tool, you will see a list of objects that you can place in the scenery. Select an object, which will change the layout to an overhead view of the world. Move the object to the desired location and click the mouse to place the object.
Select the "Edit Terrain" tool to modify the layout of the terrain. With this tool, you can increase or decrease the height of the ground to create mountains, valleys, and hills.
Click "Save" to save the changes that you have made to the FSX map.
Run FSX to view the scenery changes from above in your simulated aircraft.