You may get .psd* file of "Cold Beer Glass Illustration" Photoshop tutorial by making a donation. Put the tutorial title in "Add special instructions to seller" line of PayPal and it will be sent to you shortly.
- Make visible another base shape. And apply following settings.
- Draw a rectangular(width = 88px) in a new layer, apply Fill = 0. Load selection for the glass body shape, invert it and delete outside parts of the rectangular. Apply Gradient Overlay effect.
- Set Opacity markers, most of them is 50%, one 100% and another one is 70%.
- Create very similar stripe with following Gradient Overlay effect.