Over the past year I've been designing street apparel to sell online, and this is one example. I found this illustration of a guy sleeping in a hammock from a late 1940s sporting magazine (found art, illustrator unknown) and digitised it to create artwork for a commissioned t-shirt design for my wife's father, who is a music lover and often known to say this quote. To complete the work, I edited the facial features to more reflect his, and created a guitar in the same style to put in his lap, and instead of "snoring zzzzs" there is a wavy music bar with notes. Typeface is "Bearded Lady", a very cool retro style font. 

For people interested in acquiring this t-shirt for their own, you can find them at our new shop: https://www.etsy.com/listing/652041704/im-rocking-even-when-im-sleeping-music