Night lords lightning terror markings?

[tide of khorne]

How do you paint lightning? I\'m having a problem with getting the right shapes. Also what colour should i use: blue to white, purple to white, blue/purple to white? Advice would be very much appreciated

 

[Arctica]

Well when i painted my nightlords i started with enchanted blue base colour and highlighted up using white. The thing to bear in mind is to keep the progressive highlights within and smaller than the previous ones. As for a reference to the shape i looked at what others painted and some photos of lightning.