Start by opening a new file. Fill the background with a dark color.
Press D to get default B&W colors as foreground and background color. From filter menu select render>>clouds.
From filter menu select render>>difference clouds.
Press Ctrl+F to apply the effect again. Keep pressing Ctrl+F till you get this result.
From image menu select adjustments>>brightness/contrast.
Apply settings as shown.
Change the color mode to luminosity.
Using line shape tool create some lines.
Deselect the path layer to see the result.
Double click the layer to open layer style window and enable bevel&emboss. Apply settings as shown.
Change the color mode to vivid light.
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