Draw yet another ring with the Marquee Tool on a new layer and fill it with a color of your choice (it won't be seen). Another small Bevel and emboss on this layer as well.
Another new layer that you fill with a color of your choice above the recent layer. Use the same selection as in the previous step. Now you chose lightgrey and white as foreground and background color. After that you go to Filter>>Render>>Clouds and then Filter>>Noise>>Add Noise. Use a small amount, about 5-10%, Gaussian and Monochromatic. The last step is to push Ctrl+G to group with previous
If U deselected the transparency Ctrl-click on the layer to load the transparency and make an adjustment layer (Curves) to chrome it up a bit.
Yet another ring on a new layer inside the other ring and fill it with black.
On the same layer you put some Bevel and emboss on the black ring. Use Inner Bevel and Chisel hard.
More Tutorials: 
It is very impressive tutorial. Hard to repeat but still nice.