Basically, reflective surfaces reflect the environment around them. The shape of the object determines the image warping on its surface. You have the under plane which reflects ground and you have top side reflecting sky and other objects around it.
In this example, basic no ref chrome like surface colors, I just think of basic dirt for ground, sky for top and the darker center is distant landscape, maybe mountains that all warp with the shape of the object.
Then add a specular light or hilight - the sun that is directional or brightest at one end of object.
Easy way is to use references to give us a big clue as to how the image wraps around the form.
In a more complicated form, like a human you still break it down into smaller basic egg shapes, or organic shapes with corners.