Here are some tips.
(1) leave her alone for the next couple of days, you have only had her for a day she is probably stressed out because of the new surrounding (every cham is like that) try not to touch her or interact with her until ,just say wednesday. (2)Then try hand feeding her a worm or something she likes. She knows that food is a safe thing so by u hand feeding her she will realized the hand is a safe thing. (3)Keep the door open to her cage often. She will see you walking around and know your are safe. (4)Just stick your hand in the cage, just put ur hand in and do nothing just keep it there. She will see that ur hand is in her territory and by doing nothing (not bothering her) she will see ur hand is safe. (5) how often are you in the room that she is in? I have my chams cage in my room, which i am always in, This one is kinda the same concept of having the door open, she will see you from her cage (not bothering her) and see that your are safe. (6) when you have her out try to keep her out as long as you can w/o stressing her out. Try to do something she likes outside of her cage like eating a worm or climbing a branch. By doing thing outside of her cage she will realize that outside the cage is safe and can be fun!. (7) your cham is still a baby and their fist instinct is to run away from humans (8) BE PATIENT!! Chameleons are very timid animals and take a while for bonding and things like that, i've had my cham for over a month now and he still isnt too fond of me. He rarely has these moments where all he wants to do is be outside his cage. It takes time! and good luck with you bby girl, they are so much fun