I would recommend you contact your mentor and or vet as soon as possible, it is normal for them to slow down and relax prior to whelping, but I am sorry but if you are on here asking for very basic information, you NEED to have someone knowledgeable to assist you in delivering these pups. Whelping is not always a natural and pleasant experience, you need to keep track of placentas and pups and make sure all come out with each pup. If one is stuck you will need to know how much time is too much in between pups and when a shot of oxytocin is required.
I would recommend sitting down with your vet and getting to know the risks and warning signs that you need to know as a breeder.
Courage is being scared to death and saddling up anyways. ~John Wayne