When building your own bird cage you have the freedom to design what you want. First figure out all your measurements as to height and width and depth. The bottom of the cage should be solid to catch the birds droppings. The sides can be interwoven with pieces of rattan first in an upright position and then in an inward and outward pattern around the edges and top. Similar to a basket weave. Leave an opening on some type of hinge to allow you to let the bird(s) in and out.

To biuld a birdcage you need to choose a flooring that is easy to clean, use metal pipes for the fram and wrap a thick wire around it, put in wooden pirches that they can rest on and build a lid that they cannot push open.