I never know what the boys are going to decide to be for Halloween. It usually changes a few times over the course of the fall, so I don't even ask until about two weeks out. Big J knew exactly what he wanted to be (a Ninja) and did most of the costume himself. I spray painted an old pair of shoes black and bought a new set of ninja swords for him. Easy enough.
Inevitably, though, M-man usually decides to be something for which no official "costume" exists. This is fun for me, but also a bit stressful, as I'm generally under a time crunch. He wanted to be Pokemon Trainer Lance. So, we found a picture online and worked from there. It involved hunting for just the right pair of sweat pants, a shirt to match (which he happened to already have), some orange Washi tape (super cool stuff!!), a cape (already had from a previous Darth Vader costume), metal buttons, old boots, and spray paint! Oh, and lots of hair gel! I thought his costume turned out well. He approved. It was a job well done, and right on time, as I was doing the finishing touches on Friday afternoon. :)