Snake hands: The art of slow, sure movement. You'll get used to it, but almost every piece of handling advice involves not moving rapidly near their heads and making them feel at ease.
Don't smell like food.
A slow long tongue flicker is the calm snake flicker. Fast tongue flickers are usually fear. Long fast tongue flickers or touching a surface with the tongue and gradually getting closer while remaining fairly rigid and s shaped means it's about to eat something.
Ball pythons ball up for protection. Preparing to strike involves an s curved neck, shortening tongue flickers, and focus, usually with a little swaying
Leave her alone for the next couple weeks. She's old, give her more time to get used to her new home. She also doesn't need to eat as often because she's old, so she'll be fine.
At the end of 2 weeks, feed her. You can go ahead and handle her after her second feeding with you (10 days after the first one). Give her like 3 days to digest