It's all about patience with Tegus. If she's really new to you, like under 2 weeks, then don't bother her more than to do whatever she will tolerate. Any huffing or puffing that sounds like spitting, or bucking of her back hips, you should let her alone. That doesn't mean you don't come around, talk to her, tempt her with tasty treats....but if it's just freaking her out - you back off. She is scared, not used to her new digs, and thinks you're the predator. It really takes awhile with some of them to calm down, and trust. 2 years ago I thought Walter1 might be nuts when he told me to sit by the enclosure and just read, drink your morning tea, and talk to her calmly, without putting your hands even near her. It really does work, but they're still Tegus, that don't trust easily. That's where your patience comes in. Thank God for Walter1 !!
A lot depends on age too....I got my male in his puberty year, and it took me 10 months to calm him. Not kidding. My female was a baby and has almost never shown aggression at all. Funny though...my relationship with that male is priceless to me. He is my buddy and never shows aggression to me ever. Often, he exhales when i come toward him. He knows his ears and jowls are getting a good rub.
In the end, you're the boss. This behavior needs to challenged in time, if it keeps going. You'll prob have questions if that time comes!
Another Walter1 tidbit was "put a worn shirt in her hide". Don't expect to get that shirt to ever look good on you ever again, but it's a great way for your scent to always be present and at some point comforting that you're not the enemy. I think it works, and supports the "patience, patience, patience" effort.