Out of the bottom edge of each bag, cut a hole large enough to pull over the head like a poncho. Cut out two armholes on each bag.
Cut two piece of poster board to be signs. On the sign for the woman, write "I'M HEFTY!" and on the man's sign, write "I'M GLAD!" Tape or staple the signs on the front of the bags.
Looking for more costume ideas and Halloween projects? Check out these easy costume ideas! You can also browse through my other Halloween articles and find many Halloween crafts, games, recipes, and other activities.