Using a sketch of a girl, I digitized it using Adobe Illustrator. (Why Illustrator and not Photoshop? I wanted her in vector format so she would scale up or down without distortion. She can then be re-formatted easily for use across web, mobile, print, textiles, etc.)
I drew in an iPhone and ear buds, and toned up her arms while I was at it. (No reason why she can’t be strong and feminine, right?) I called her Nerdy Nelly.
Experimenting with different sizes and degrees of overlap, I came up with a pattern that looks—at first glance—like a conservative herringbone pattern. (Herringbone is very in this season, BTW). Only upon closer inspection can you de-code it to see that it’s an image of a girl on her phone. Surprise!