Stencil color image on a shirt w/ similar pattern

By Old Navy

Awesome use of white

By nevedobson on Etsy.  Also look at all her animals.  Or basically everything she's done...

Robot stencil

At RockRiverTees on Etsy

Etch-a-Sketch

By RockRiverTees on Etsy

Piping

By Mme Zsazsa

Octopus, Rocket, Jolly Roger

Applique templates at Crap I've Made

T-shirt with button shirt combo

From Maeve magazine

Animal Novelty by Timeless Treasures

A Dog's Life in Khaki

Dog Lineup in Neutral

Dog Lineup in White

Tossed Dogs and Bones in Khaki