This question was just asked on /r/tegu & I thought tumbler reptile people might also find the answer useful:
We have a 5-6 month old red Paraguayan Tegu, Vada.
When in her enclosure, she is calm, inquisitive, doesn’t mind being handled a bit, etc. But when we let her roam the house, any movement toward her or around her spooks her. Even trying to slowly pick her up to put her back into her cage causes her to try to flee.
I’ve just started to try to spend an hour each day sitting in our bathtub with her so she gets used to me. I also throw in a worn shirt into her enclosure every so often.
Are there other techniques I ought to be doing? Would just letting her roam around, free of distractions and interruptions, be beneficial? What else can I try?
It’s normal for them to be extra scared and cautious of things moving around in a new environment. What you want to do with roaming is basically a larger scale version of how you get her used to you in her enclosure. When she’s in the enclosure, you start off by sitting next to the enclosure… move up to putting your hands in the enclosure but not near her… then move up to getting close to her but not touching her… then gently rubbing her head, etc…
The roaming version is basically the same, but with your whole body and not just your hand. First you want to get her used to your walking around, not towards her, on the other side of the room. Then you want to do some diagonal like paths that are not directly towards her, but where ur getting closer to her… etc. Then you want to get her used to things happening above her, like hands moving around, but not picking her up… etc..
Basically you want to try and get away with as much as possible, but without spooking her. Just keeping doing the most that u can get away with, and then the limits of where that is will change.