Thanks Pat

You won't need to sterilize the whole tank. It should be ok. Pour some boiling water on the twigs then let them dry and it should be ample

As Patsy said, if her abdomen is dark she is coming upto a moult. Don't feed her, she won't eat and any crickets left in there could chomp on her so remove any live food still in there. I always make mine a bit more humid when i know they're going to moult. So over flow her water dish and it will be fine Then just leave her to it, there's nothing else you can do.
Good luck