Gradient’s parameters:
Blending Options>Stroke 
Gradient’s parameters: 
Using the
Ellipse Tool (U), it’s possible to draw a highlight on the button demonstrated below:
The layer’s parameters:
Fill 0% Blending Options>Gradient Overlay 
Gradient’s parameters: 
The symbol on the button from below is done with the
Rectangle Tool (U), by holding the
SHIFT button. The color is white.
The layer’s parameters:
Blending Options>Stroke
On the play button’s panel we’ll introduce the indicator itself, colored with
#017CC5, made with the
Rounded Rectangle Tool (U) with a radius of
10 px and then press
Alt button while applying the
Rectangle Tool (U) to make a cut on the right side.
