Transparent Glass

1. Start by create a new document 150 x 200 and fill the background with a light colour (#E7DECE).

Create a new layer and make a sircle with the Elliptical Marquee Tool (M). Fill the selection with white. Deselect.

2. Now it's time to get some colour on it. Apply a gradient overlay. To do this go to Layer > Layer Style > Gradient Overlay and use these settings:

Blend Mode: Normal
Opacity: 50%
Style: Linear
Angle: 128
Scale: 100%
Gradient: #000066 (dark blue) and #3399FF

3. To make some depth to it we will apply some Bevel and Emboss. Go to Layer > Layer Style > Bevel and Emboss and use these settings:

Style: Inner Bevel
Size: 5 px
Angle: 128
Attitude: 50
Shadow Mode: Normal, # 000099

4. Apply Contour, Layer > Layer Style > Bevel and Emboss.

Select Contour

Conture: Cone
Range: 50%

5. The last thing we have to do is to change the fill opasity to about 40 % and we are done.