so I am a volunteer at Zany Zoo, and they want me to come in as often as possible to handle their Tegu monitor Tena, she's sort of aggressive until you get her out. I am their to get Tena used to people so she can be a part of the petting Zoo. how do I do this. Usually I just hold her and calm her down. sometimes let her roam around if no customers are browsing the area. I've gotten her to the point where she will cuddle on my shoulder and go to sleep, SOMETIMES.... but she is still sometimes aggressive... what do I do?