Do one of the following:
In a part document, choose Home tab→Planes group→Coordinate System.
In an assembly document, choose Features tab→Planes group→Coordinate System.
In the graphics window, click to specify the origin for the new coordinate system.
Tip:
You can place a coordinate system relative to model geometry, another coordinate system, or in empty space.
When you select an existing coordinate system, you can use the commands on the shortcut menu to show, hide, edit, rename, and delete the coordinate system.