I will be using photoshop for the quick sketch and illustrator for the line art and colours.
Fist I start off with doing a quick sketch in light blue. Light blue is just about visible but will not get on the way when I ink the piece (using dark colours can make it more difficult when moving on to the final line art as I find it tends to look similar to black ink.
Next I create the line art. In illustrator I use the blob brush tool (cmd + B) and just draw the outlines on the quick sketch. The quick sketch is then removed as I no longer need it.
With the line art complete I then proceed to adding the colours. There are several ways of doing this in illustrator but I use the blob brush tool.
Now it is just the shadows.
Finally I add the background and we are done.
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