...I know that is easier said than done and I just wish you were more prepared. They can lay as early as 6 months espceially if overfed, but we can discuss your setup later.
The substrate may not be sufficient or is not deep enough. It needs to be at the very minimum as deep as she is long and same wide or better if deeper and wider. How big is the container? It also needs to hold a tunnel well - stick your finger into it to make sure it will not collapse. She also needs to be left alone. Did you read the article I linked you to from your original post on subforum?? I would suggest using that method - read the whole article, it is not long and has photos. Did you read kinyonga's reply to you there, too? You can get playsand at home depot for about $3 for a 50lb bag. I mix mine with coco-fiber, or you can use peat or use it alone.
When did you notice color change? size? not eating? I ask to try and get an idea of how far along she is.
Most importantly - do you have a qualified vet? There is a good chance you will need one. If not, go to the link below and check out the links to vet listing for your state/province.
So read the article www.chameleonnews.com/year2003/jan2003/nesting/nesting.html
set her as described. You don't need to palnt the ficus tree or put the leaves on top as your situation is dire and you don't have time to fuss - but USE BETTER SUBSTRATE, offer her water if she will take it, then leave her alone.
See the post just below this one Preperations for Gravid female...any other advice? for some more tips.
After you have gotten her all fixed up just cover the setup and look only occasionally to make sure she is digging,. She might dig a few trial holes, but let ehr do it - DO NOT interrupt her. The entire process can take several hours to overnight.
keep us posted and try to stay calm - for her sake 
lele

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