Recently did an illustration of the band 
Ravens and Chimes for 
Amelia's Magazine. Here's the process:
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| Draw the band from a promo photo on their website | 
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| Draw some ravens in flight, using Google Images as a source. | 
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| In Photoshop, create a background by rotating and pasting the ravens image, and add the band drawing in the foreground. | 
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| Print out the combined image and paint the background. Printer ink mixes with the watercolour and makes unexpected hues and shadows. | 
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| Crop the image, bump contrasts and levels: Final image. |