The layer’s parameters:
Blending Options>Gradient Overlay
Gradient’s parameters: 
Make a copy of the recently made layer and choose again the
Free Transform option to turn the copy over and place it the way it is represented on the next picture. Its color should be
#C6C6C6 
Make a copy of the last made layer and select the
Free Transform option to turn around the copy and place it on the same position it is demonstrated below. The shape may be corrected with the
Convert Point Tool.
Make a copy of the last made layer and turn it over, selecting previously the
Free Transform option, placing the copy the way you may see below.
The layer’s parameters:
Blending Options>Gradient Overlay 
Gradient’s parameters: 
