Gradient’s parameters.

Merge down now all the layers, composing the button in a group and copy this new made group.
Using the Free Transform selection, turn it around on 180 degrees horizontally and place everything out the same way it is shown next step.

Add then two triangles that must look exactly the same way with those created before.

Using the next tool , insert a new circle with this parameters demonstrated next image.

Blending Options-Gradient Overlay

Gradient’s parameters.

Take the same tool and create a circle of black color with the parameters shown below.