1. Make a new picture (CTRL+N) i used the format 477x477 pixels. This techinque is ONLY working with rectangular images (width=height).
2. Press 'D' to reset the colors
3. Click on 'Gradient Tool' and set 'Foreground to Background', and set Mode to Difference. (look at the image below)
4. Now just make alot of gradients in the image until the whole image is filled with gradients.
Your image should now look something like this:
You will now have two layers. You are now done with the design, I will now teach you how to make magic with the blend mode Lighten.
5. Duplicate your 'Background' layer by rightclicking on it and choose 'Duplicate Layer'.
6. Click on Edit > Transform > Flip Horizontal. We will now start making the lightning effects. Change the blend mode to lighten. (look at the image below)
7. We will not make the two layers to one and include the blend mode. To do that, click on Layer > Flatten Image.
8. Now you have one layer, the Background layer. Duplicate this, just like you duplicated the other layer before.
9. Click on Edit > Transform > Flip Vertical, and again, set the blend mode of your new layer to 'Lighten'. Your image should now look something like this:
10. We will now make it even more 'electric' so again, we flatten the image, duplicate the Background layer. And this time you should click on Edit > Transform > Rotate 90 CW. Change the blendmode of your new layer to 'Lighten'. And you should have something like this:
11. Now its time to colorize the image. But first, you need to flatten the image again so both layers will be colorized. Press CTRL+U and the Hue windows till popup. Check the Colorize box in the down right corner and change the 'Hue' and 'Saturation' until you like the colors. (I use Hue:200 and Saturation:50)
Here is my final image:
