Yeah once they start scratching its time. Normally, you can feel the eggs, like marbles in their belly. I had a female this year her first clutch, I couldnt feel, but she was scratching so I put her in the egg laying bin and she laid an infertile clutch. They were all soft. I like to use a seperate container for the egg laying. Its a big rubbermaid(like the 40 gallon or something), that I fill almost all the way up on one side with a mix of dirt/sand and make it moist. I then slope it down towards the other side. I start my own tunnel into the side of the hill, and usually thats what the female uses. I cut the cover for the tub in half, and cover the high side. The low side I put a clamp lamp to give some heat/light down into the tub. Just my setup, I know people use all different setups.
Chris