Make a tripod from dowel rods. Your dowels should be about 1 foot long. Use dowels that are only one-eighth to one-quarter inch in thickness, so you can cut them with scissors. Use a piece of duct tape to hold them together at the apex. Cut cross pieces to connect the legs of your tripod at the bottom. Place each cross piece so that it touches the end of two legs. Tape these with duct tape.
Cut chicken wire into triangles. Use wire cutters for this. Make the triangles approximately the same size as the sides of the pyramid frame, but just slightly larger. Attach them by bending the cut wires around the dowel rods. You should end up with a piece that is in the shape of a pyramid with chicken-wire sides.
Papier-mache newspaper strips over the wire. Make papier-mache glue by mixing flour and water until it forms a paste. Dip newspaper strips in it and lay them over the chicken wire. This will make a solid foundation for your plaster of Paris. Allow the papier-mache strips to dry completely.
Apply plaster of Paris with a spatula. Smooth it over the newspaper strips like you would frosting on a cake. Make the surface as smooth as possible. Allow to dry. Look for any cracks that have to be repaired and cover them with a thin layer of plaster of Paris.
Paint the entire surface a light brown. Look at pictures of pyramids to see the approximate color. It should be a sandy brown.
Paint brick shapes on the dried plaster of Paris, using black or brown paint. Look at a picture of a pyramid as you do this. Notice that the blocks that make a pyramid are not all the same size. Mimic the smaller-size blocks as you paint your way to the top of your pyramid.