This simple superhero onesie costume by Ann Marie of White House Black Shutters is adorable. You only need a plain white onesie and a few basic supplies like cardboard, spray paint, and a tshirt to make this entire costume. You could make a whole family of superheros or just dress up the baby.
I love how all of the pink coordinates, and I especially love the superhero initial. Visit White House Black Shutters for the full tutorial.