6
Return to your Layers Window, make a new layer. Press Ctrl+Alt+4 (Mac: Command+Option+4) to load your Alpha channel. Select medium gray color for your foreground and then press Ctrl+Del (Mac: Command+Del) to fill the selection. Press Ctrl+D (Mac: Command+D) to deselect.
7
You may want to add more shapes to your interface, before adding the bevels. Use round rectangle tool to add more buttons and other shapes to your interface.
8
Now is the fun part :)) -- adding the bevel. Go ahead and make a new layer above your interface. Ctrl+Click (Mac: Command+Click) on your interface layer to load it's transparency (selection). Go to Select>Modify>Contract, enter 2px for the value, click OK.
Select white for your foreground color then fill your selection. Lastly, go to Filter>Blur>Guassian Blur and enter 2px for the blur radius, click OK and then deselect.
9
Now we need to add layer styles to make a good looking bevel. Press on the "F" icon at the bottom of your Layers window and choose Bevel and Emboss..Click here to see how your settings should look like.
10
Now we need to fill in the white spaces with some gradients. First of all, click inside your main window with the Magic Wand tool to make a selection. Go to Select>Modify>Contract, enter 2px, click OK. You're now ready to fill your main window.
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