How To: Easy Stick on Digital Camo Stencils - Camouflage Week
At first I was skeptical of the methods this guy employs, but the end result is a nice looking camouflage pattern with easy application.
Creating the stencils:
Three-toned pattern application:
The only change I would make is the use of Krylon's Camouflage Paint with Fusion Technology, which has the reputation of being one of the better camo paints out there. Also, I wouldn't use a nice printer with this method, because there's always the chance you'll brick your printer with a few errant pieces of painter's tape/wax paper.