Males can be bred at 100 grams. Females need to be at least 300.

I just put the female and the male in a tub together and leave for an hour or so. You'll see evidence of a successful lock; you should use newspaper as a substrate in the breeding tub. When they are together, one or both will start shivering if they are responsive. It shouldn't take longer than and hour, mabe even 15 minutes, for them to lock up. But after an hour if they are still chasing or acting like they should, just leave them for longer. That's all I did and I should have eggs in a few days. (I paired them really late)