I thought I'd include some of the steps involved in making this image, since I like it so much.
First, I draw out the rough sketch idea, using a light grey colour. The idea is to simulate pencils, even though I draw directly onto my computer.
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The next step is to soldify the lines and then draw over them on a new layer, in black. (The inks).
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Finally, colour and shade to taste. Add background and then we're done.
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Alas, that's way too quick a summary of a process that takes several hours over several days to complete. Still, I'm considering putting this on a t-shirt (for women, at least). Baby pink and black backgrounds.