What kind of chameleon do have that is gravid? Do you have any pictures? Did you see her mate? Most people use a separate large tuperware type container (a couple feet long by around one foot wide should do fine.)with about 10 to 12 inches of moist padded down substrate. Some use sand some potting soil etc.
Put her in there for a few hours to see if she will start to dig. A heat light may be used on one side of the container to keep her comfortable. If she doesn't start to lay after a few hours, take her out and try again in a day or two.
I always keep an opaque container of washed playsand in any sexually mature egglaying female's cage so she has a place to dig to let you know that she needs to lay eggs. Some of them will lay in this container and others will need to be moved to a larger one. Once I put the female in the larger one, I leave her there usually until she lays the eggs. I don't like to move them back and forth.
Once the female is digging, you should not let her see you watching her when she is digging. It will cause her to abandon the hole thinking its unsafe. If it happens often enough it leads to eggbinding. Its okay for her to see you when she is up in the branches.
The female may dig one hole for more than a day or dig several test holes and settle on one. She should eventually turn around bum down and lay the eggs. She should bury them and then return to the branches...at which point you can dig them up.
You can still feed and water her when she is up in the branches, but make sure that you remove any uneaten insects so they won't bite the chameleon or the eggs.
Good luck!
Maybe "gravid" was the wrong term... It is a veiled, she hasn't been bred, so I guess I should have said 'an infertile clutch?' I dunno.
Anyway, she hasn't been bred, but sure has the symptoms of an infertile clutch and I've been noticing her starting to look preggo before this started. I guess I should feel for eggs but I'm half-scared to poke at her, she's pretty vicious haha.
im not quite sue what to suggest, i keep veileds and other chams but all males exsactly for the reason you mentioned(risk of egg binding) put a large digging cat tray size tub with correct digging like coconut fibre or washed sand mixed with a little organic soil substrate,keep it very slightly damp not wet!!!in her enclosure as suggested above and perhaps seek advise from the vet as he will know best of what to do...dont leave it though as there is the risk of egg binding with female chams if left for ages and this can kill chams. im sure its fine at the mo but best to ask so you dont have to worry,im sorry i couldnt offer more info but dont have any females ...yet! good luck