Couple fake trees and/or skulls from petsmart. Also check out Hobby Lobby for some fake garland that you can cut apart and make trees and vines with. All these things make dark shadows, crevices, and keep the animal from feeling exposed. here's an example of my 20 gallon long that contains my hatchling blood python. You can use a large enclosure. You just have to make the extra effort to make your animal feel secure to roam.