This can be dangerous ground but as the breeder you must do all you can to put into a growing litter everything they need. Every individual has their own opinion and I am not at all suggesting that they are wrong and I am right. Here is what I found to be successful.
I have a whelping box which is roomy but not too big for the mother to lose her pups. I have a pig rail insert for the first few days but I find often need to remove it when the pups start moving around. It has newspapers and a large piece of vet bed which is changed daily.
Once the litter are born I keep the mother and pups in a quiet area (some may call this our dining room) away from other dogs but not too far away to be totally isolated. There she can hear the sounds of every day life and not be stressed by it being too quiet. I make sure she is well fed and has plenty of clean water. I also ensure she and her pups are warm, not over hot, to make her move away from the litter. I use back ground heat rather than a heat lamp or heated blankets, although I do use a crock hot water bottle to begin with. I feel that Scotties can generate their own heat to maintain the temperature of the pups. Incidentally, we always use a heat pad with the Griffons and Toy Poodles.
I rely on mother to look after the pups as I fee she often knows best but the pups are not left unattended for long periods. Their growth is monitored and any signs of lack of growth results in an immediate reaction on my part, eg. making sure is feeding off her and putting smaller or weaker pups onto her most productive teats. I do supplement if I think it necessary.
When the pups are older and aware of their surroundings I introduce a radio into the room. I prefer a station with conversation as well as music and often tune it in so the reception is not perfect so it crackles, mimicking a loud speaker at dog shows.
Food is introduced from three to four weeks depending on the litter. I think it can be a mistake to offer food too early. The first food is usually minced beef, pressed between my fingers so it is thin and easily put in front of each pup. They do not take too long to accept this. I use some milky foods but find if this is overdone the pups can become covered in dandruff so I use cheese as a milk substitute. During this time of rapid growth, I think the pups need bulk and make sure they have it. At this time, I frequently change the bedding and newspapers so everything remains fresh. I extend the whelping box so she can move away from the pups and they can begin to explore. by the time the pups are six weeks, the mother is usually taken away from them but allowed to see them at frequent intervals so they do not lose all contact.
Outside play with the pups is important to both mum and babies. As the pups get older they are moved into an area where they are able to see and hear more of everyday life.
This is an outline of how I rear a litter and it works for me. The most important point is that the pups are warm, well fed, watered and socialised before going to a new home. When they leave, I always send them with a full list of the food they have been reared on to prevent any risk of stomach upsets.