She's a veiled chameleon. Well, hopefully she isn't too anti-social. I was told by the guy at the pet store that they're fairly sociable. Maybe he wasn't too knowledgeable. Do lighter colours mean better moods? Or does it depend on the chameleon.
Just like what everybody has said, these beautiful creatures are mostly solitary.
Respect their space, and you have won half the battle of not getting bit.
When a veiled doesn't want to get out, it doesn't want to get out period.
Don't force them or they'll let you have the consequence.
when you respect them, give them food water and everything they need, eventually (or not -depending on their personalities), they will learn to associate you with good events.
I never "handle" or try to "tame" my chameleon.
Slowly they learn that my presence means food, water, and occasional sunbathe opportunity. All my chameleons with the exception of 1 tolerates my presence.
I would reevaluate everything that the "reptile staff" told you.
They often just blab without having to know how to care for chameleon.
The secret to their "expertise" is by pretending they know a Lot of stuffs.
Unfortunately, their "knowledge" often bring demise to the chameleons.
And Welcome to the forum.

Hope you enjoy the ride. And, be careful. Chameleon is addictive.