16. Now make your background invisible;
-Merge visible layers (Ctrl+Shift+E);
-Edit--->Transform--->Rotate 90°CW;
-Copy layer;
-Change Blend Mode of the top layer to Overlay.
17. Again Merge 2 layers with our spikes. (Ctrl+E). And copy layer. So you have now: background layer (white) and 2 layers with spikes.
Rotate the top layer 90°CW again (On step 19 you can see my layer palette).
18. On the top layer apply the Wave filter with default settings. (Filter--->Distort--->Wave).
19. Fill your background with black. Not too bad, huh?
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