Purchase a series of sockets from the local hardware store. Whether you choose white or black sockets will depend on the look you wish to create. Alternatively, you can use a combination of black and white sockets.
Take the first Y-socket and screw another Y-socket into each open end. Keep adding more Y-sockets to the open ends, leaving some empty, reserved for the light bulbs. The size of chandelier you build will depend on the look you're after. The resulting shapes will be branches extending from the original socket.
Build the socket chandelier to the desired size. Add the light bulbs to the chandelier wherever there is an open socket. You might need to make adjustments to ensure there is a balance of branches and open sockets.
Screw the finished chandelier into the open socket in your ceiling. If the size of the chandelier isn't right, remove the chandelier and re-assemble it until you're pleased with the design. Larger spaces may require a bigger chandelier.