The OP asked a question & I don't think it's been answered? Unless it was done via PM...
from the web:
https://www.google.com/search?q=how+...YQ_AUoAA&dpr=1
videos:
https://www.google.com/search?q=how+...+puppy&tbm=vid
Most experienced breeders cut & tie the umbilical cord themselves, it prevents umbilical hernias. Let the momma clean her puppies, but you need to assist her through the whole process. Don't let her eat more than 2 placentas, if she eats too much or all of them, she will get diarrhea. Know the distress signs & have a vet or emergency vet on speed dial.
Please read through this site if you haven't:
Canine Reproduction Video and Book on Breeding and Whelping dogs by Debbie Jensen for dog breeders and Whelping Supplies needed to deliver puppies.
All the Best for a safe whelp!