Gradient?s parameters:

Creating emoticon in Photoshop CS

Select the used before instrument and draw a circle.

Creating emoticon in Photoshop CS

Blending Options-Inner
Shadow

Creating emoticon in Photoshop CS

Blending Options-Bevel and Emboss

Creating emoticon in Photoshop CS

Blending Options-Gradient Overlay

Creating emoticon in Photoshop CS