You can use aluminum screening material; however, I have read/ seen chameleons that climb the screen and consequently rip their nails out. I have not experienced this as of yet, but if I were to build an enclosure, I would use 1/8" hardware cloth. I would use the cloth on the two side panels and top. I would use thin plexi, or glass on the front and possibly the back. You might take a look at dragonstrand cages. I see that they are now using a transparent, durable plastic material ( kind of like convertible top window material) on their cages.