Have your birthing box ready and let your girl get use to it around two to three weeks before puppies are due. For small/toy breeds a large box with top that can be remove during the birth of puppies. Place newspapers at the bottom and then puppy pads or towels. Make a layers so you can remove one at a time after a pup is born to keep the area clean and dry. I have one female that will get so worried about the area being clean she will take longer to have the rest of the puppies. But if I keep the area clean she will get back to having the puppies. Puppy pads or pads for incontinence. Some breeders even use them in the puppy pens as a potty area. They are about 36" x 36" and can be wash and used over and over.
You should have a Warming box ready so no need to have a heating pad in with Mom having the pups. The last thing you want to do is heat up the mom during birth of the puppies.