I've had this flask for a few years that I got as a gift and never particularly liked because I don't like pink. So I cut out stencils and decorated the front and back. I used a permanent marker because I didn't want the spray paint to run on the smooth surface. You can find some really sick designs at stencilpunks.org
Caitydid posted this project as a creation without steps
Here are some similar tutorials to help you make this one!