Papier-Mâché
The beauty of papier-mâché is that it is cheap, lightweight and malleable. When watered-down PVA is used as an adhesive, papier-mâché is also waterproof, making it an ideal substance for creating cheap goose decoys. Water down the PVA using one part water to five parts PVA. You will need to make a frame for the decoy. A soda bottle makes for a good goose body, and you can use a wine cork pierced with a piece of wire and mounted on the top of the bottle as the head. Soak newspaper strips in the PVA. Wrap the strips around the frame to build up the model goose and allow it to dry. Once dry, spray the surface with a white base coat to provide a textured surface to paint on. Study a reference picture of the goose you wish to attract and mimic its coloring and patterns.
Rubber
A decoy made with liquid rubber can be slightly awkward to create, but the finished product is buoyant and resilient. To make a rubber decoy, create a clay, model goose and cut it in half. Create plaster casts of the halves. The awkward part can be attaching the halves with liquid rubber because it is easy to leave gaps that prevent the decoy from being watertight. To address this potential problem, sand the joint so that the halves are flush and seal the joint with bathroom sealant; the decoy should be watertight.
Wooden
A wooden decoy is the most traditional of goose decoys, but it takes an element of craftsmanship to get it right. Carve the basic shape of a goose from basswood, which is lightweight and well-suited to carving. Cut broad and jagged strokes until you have a block about 12 inches long with a tapered end and a head end. Use a lathe or belt sander to smooth the edges into the sleeker shape of a goose's feathers. The wood will need lacquering and coating with preserver before being used as a floating decoy. A more detailed goose carving can be made using layers of wood.
Trash Bag
If you are looking to create a decoy on a limited budget, and not for use on water, a trash-bag decoy is an option. Open between 12 and 20 white trash bags and anchor them in a field or other open space so that they look like flapping wings in the breeze. Vacate the area and watch from a distance. The billowing, white plastic is supposed to look like a flock of birds and hopefully will attract geese.