Ok so since no one answered the rest of your questions.
1. once a female breeds it takes 30-45 days for her to lay, since you don't know when she bred, get a lay bin in her cage now.
2. you want a bucket 12 inches deep and 10-12 wide, filled with moist (not wet) dirt or sand or combo of both. it should be wet enough to dig a tunnel and have it hold the shape.
3. eventually she may go off food, which is a good sign she needs to lay. Once she starts to dig, leave her alone, don't touch her, go near her, spy etc. nothing. if you interrupt it can lead to egg binding. which requires a vet and surgery.
4. its ok if you find her asleep in the tunnel she dug, totally normal. It can take her 1-3ish days for her to get a good tunnel dug and lay.
5. for incubating, perlite or vermiculite is totally fine. you want it wet enough that you can squeeze a drop or two of water out of a fistful of it. once the eggs are all laid, and youre sure shes done, you can dig the eggs up, an dplace them in the container of whatever you used. just make a small divet in the top, and place the egg in it. Once placed, DO NOT roll the egg. the baby can drown if you do this after a certain point.
6. place the entire container in a warm closet, no more than 76 deg, and then just check the moisture levels every few days from now till they hatch (which takes 6-9 months, usually closer to 9)
7. youll want to make sure she gets good quality food and calcium, because if she doesn't have that, the eggs will steal the calcium from her bones.
8. 3 bugs is too little. I would do around 6 bugs every day to every other day, depending on her eating habits.
if you have any questions, feel free to PM me.
Good luck!
