If you want to create an artificial environment for a pet reptile there are a few things you should think about.
- Where is it found in the wild?
- What does it eat?
- How big will it get?
- Will you be housing more than one together?
What it eats will determine what you can put in with it as far as live or plastic plants or another companion. You will also need to think about availability and expense of food like crickets, meal worms, lettuce, rodents or even other reptiles.
How big it will get will help you decide how much time and money to spend on a cage that your reptile might outgrow. Also if you will be housing more than one you will need to know how much space each one will need. Here is a good book about building reptile vivaria.