1) Make a new file 100x100.
2) Add a new layer.
3) Using the selection tool on elliptical, make a circle. Select a foreground and background color and fill the circle. (Fig1)
4) Select Filters/Render/Lighting. Select the style as "Flash". Then narrow the focus of the light by dragging the edges towards the center. Drag the focus of the light into a position on the upper right side of the image. (Fig 2) Change the Intensity to 35, the Gloss to 45. Click ok.
6) Add layer effect Drop shadow.

Now you are done making cool ball icons...

1) Using the selection tool on elliptical, make a circle. Select a foreground and background color. Always select the darker color for background color and a lighter color for foreground color.(Here I have selected foreground and background colors as FAD923 & 9D0606).
2) Select the radial gradient tool. Drag the tool from top left to bottom right.Hold down the Shift key while dragging to draw in 45 degree angle.(Fig 4)
3) Then add the layer effect Drop Shadow.