Photoshop Glass Button

The following steps are required to give a glass effect to buttons:

1. Select two appropriate colours (for gradient shades)
   
   
   
   
2. Select Rounded Rectangular tool:
   
   
   
   
3. Draw a simple ellipse:
   
   
   
   
4. Create a new layer:
   
   
   
   
5. Ctrl + Click on the vector mask in the first shape layer so that you can select only the ellipse:
   
   
   
   
   
   
6. Select the Gradient Tool:
   
   
   
   
7. Make sure that the gradient consists of the two colours you have already selected (you can find this in the top left corner under the menu):
   
   
   
   
8. Select the new layer while the ellipse marquee is still highlighted, and draw a gradient from top to bottom:
   
   
   
   
9. Optionally, an inner glow can give a nicer effect to the shape by right clicking the second layer, and selecting "Blending Options":
   
   
   
   You can tweek the above settings for colour, size, and opacity of the glow.
   
   
10. Click OK, and review the effects of the blend:
    
    
    
    Note: the ellipse marquee selection should not be un-selected at this point.
    
    
11. Create a new third layer:
    
    
    
    
12. Select the Elliptical Marquee tool:
    
    
    
    
13. From the top-left settings under the menu, select the intersect option:
    
    
    
    
14. Draw an ellipse marquee selection outside the image to intersect with the top half of the image:
    
    
    
    
15. Change your primary colour to white, then select the gradient tool with the white to transparent setting in the top-left corner under the menu:
    
    
    
    
16. Draw a gradient on the new layer from top to bottom as shown below:
    
    
    
    
17. Finally, deselect the marquee and review the image:
    
    
    
    

This can now work as a button image as shown in the below example: