Scratch

Just wanted to tell everyone.

1. Make a new image with size 640x400.
2. Click Filters > Render > Clouds > Difference Clouds, click "New Seed" and click OK.
3. Make a new layer and fill it black, put it behind the clouds.
4. Use the "Fuzzy Select Tool" and select some areas. Then press the "delete" key on the keyboard.
4a. Make now a copy of the layer and work with the copy.
5. Fill the areas with blue. REMEMBER: The brighter the gray, the brighter the blue!
6. Click Filters > Map > Illusion, set Divisions to 5.
7. If it's too dark, make a new layer and fill it white. Then set the opacity to 20.

Done!