The premise was to customize this shoe model in any way you wanted. The media I chose was watercolour, although, if the shoe was to be produced, fabric would be printed digitally. 

I used salt (just regular cooking salt) to create the bleached areas and simulate whale skin and the little crusty rough looking surface) apparently, salt chemiaclly reacts to the minerals and metals contained in watercolour creating those bleachy star-shaped stains.

I just needed to draw a full body whale after that texture discovery :D

and got carried away with the bleachy stains, just for fun.