Here is the way I do it. It has always worked for me and I have had 7 clutches. I have a lay box that is about the size of a beer cooler, 2.5 ft X 1.5 ft X 1.5 ft. I fill it about 1/2 full with the coconut fiber, moistened and lightly packed so it won't cave in on your beardie. I put the lizard into the chamber, then put the cover on the chamber. It doesnt "seal" so it will provide enough air for her to breathe. I make sure it is at least 70 degrees F in the room and leave her alone for a couple days. Lack of light will not be an issue for a few days. She will get used to it, do her thing and it will be over. Babying them and moving them from one place to another does not cut it. A lay box has to be big enough for the animal to move around a bit. If the store does not have a tote this big, use a beer cooler. I know they have them in the UK. I hope this helps you.
Bill
Bill