With livebearers once the female is pregnant its not too much work to prepare for the frys. When she is really ripe you can see little black eye balls in the rear end section of her tummy. Usually when you are able to see that she will be more than likely to deliver.
If there is still a fry in the breeder net I don't recommend you placing her in there, she will eat the fry in there. Its best if you remove all the other fish out of that tank if there aren;t too many of them, or remove the pregant female into another tank. If you plan on using a breeder net make sure you are using the ones with the mini holes on the sides n bottom so the frys will be able to swim out, because if you use one of those green mesh fry nets, the will eat them up once she delivers them.
I have bred varies livebearers for a few years a while back so if you have any more questions you think I may be able to help with, please feel free to send me an email at email@example.com
o, n crank up the temperate to abotu 80- 82 degre F, it'll help induce her to give birth faster.