Apply the here shown
Rectangle Tool (U) to represent a stripe to put the key in.

The layer’s parameters:
Blending Options>Gradient Overlay
Gradient’s parameters: 

The last stage includes representing a flare of white color on the upper part of the stripe the key is situated in. the operation may be done with the
Line Tool (U).

The layer’s parameters:
Blending Options>Drop Shadow


The icon is finished!