My son Sean was an upside down old man. My husband doubted that we could pull this costume off, I am so glad we proved him wrong!! We bought men’s pajama bottoms and a windbreaker jacket at a thrift store. They were oversized, but needed to be. We had him wear the jacket as pants and put the pants over his head with his arms through them. His head fit into the one side of the pant leg. We cut small holes for his eyes and mouth to breathe. I needed to sew the jacket so it wasn’t so big in the middle and would fit better. I stuffed the hood with fiber-fil and sewed a mask onto it. I also needed to sew the hood to a higher point of the jacket so it didn’t drag on the ground. I took a thick piece of elastic so it would fit snug on his chest to keep the jacket from falling down. I think I learned if I was to do an upsidedown costume again, I would make some sort of board to fit on his back to make fake arms. It wasn’t realistic for him to have his arms up all the time. The best part of this costume was the reaction he got when walking in it. It was equally funny from the front and back. Many many double takes. We had lots of fun with this.