2. Click on the 'Ellipse Tool'. (look at the image below)
3. Press SHFT and draw a circle on your image. (look at the image below)
4. Double-click on the layer, to get the blending options window up. Click on Gradient Overlay', set Anlge to 135 and Scale to 150, OK
5. Duplicate the layer (by draging it to the 'Create New Layer' button in the Layers-window.
6. Press 'M' to deselect the 'Ellipse Tool'. Press CTRL+T to transform, set W: to 90% and H: to 90%. (look at the image below)

7. Double-click inside the box in your image to accept.
8. Double-click on the second layer to get the blending options window up. Click on 'Gradient Overlay' and set Angle to -45, OK.
Your image should now look like this:

9. Duplicate the second layer, select the third layer, press CTRL+T to transform, this time user W: 97% and H: 97%, accept.
10. Double-click on the third layer to get the blending options window up. Click on 'Color Overlay', click on the colorbox and select the color you want.
11. Click on 'Bevel and Emboss' set Depth to 50, OK.
You will now have a nice button, you can now add text in it or whatever you want. Here is my final result:













More Photoshop: