Do some google searches. I know that I found an awesome photo essay of a vivarium upgrade showing the progress. Obviously, I second everything from Kurt!

Oh, and I will say that we've had some great luck with the plastic branches that you can buy for aquariums! Just be sure to plug up any big holes. Our little Kibbits liked to crawl inside and sleep, which although cute, was a pain to lure him out come feeding time. We learned our lesson!