Perhaps, rather obviously, in the early stages of puppy development, it is particularly important to ensure that the coat is kept clean and free from knots. Additionally, it is helpful to accustom the puppy to being washed and dried so it is part of their normal routine.
From personal experience, I have found that regular combing of the puppy's coat has had a twofold benefit. First and foremost, this regular combing process helps the puppy to become used to a slightly heavier grooming session than just brushing, whilst ensuring that the coat is completely "knot free" to the skin. The second benefit is that the regular combing process helps to remove the older puppy coat and stimulate the growth of the coat generally, as well as helping the change towards the next stage of coat change which is commonly recognised as the "Junior" coat. Some years ago, I focused more upon the dark coat for this combing process as that is where the change is seen, but again on a personal basis, I have found that by "total" combing of both the dark and white coats, a balance of coat growth is achieved across the whole of the puppy's coat.
During these early familiarisation processes, the puppy should also start to experience some of the regular hygiene processes that will continue throughout their lives. The coat should be carefully trimmed around the anus and genital areas, taking great care not to cut the puppy (rounded end scissors are best, not sharp pointed ones). The trimming around the anus should not be excessive and should be proportionate to their size, with an adult dog requiring approximately 1" (25 cms) of trimming around the anus. The hair between the pads should be carefully checked and combed to ensure that there are no knots between the pads and the hair either trimmed flush with the pads or trimmed out completely depending upon personal preference. Whilst working on the pads, the nails should be checked and when necessary cut and filed to an appropriate length. The attention to the nails is particularly important during the puppy period due to the limited exercise and the sharpness of the young claws. Next, you can check the ears to ensure they are clean, carefully wiping the flap with a moist tissue but never inserting anything into the ear canal. In the event of excessive build up in the ears, or a strong smell developing, you should consult veterinary advice. Finally with regard to the ears, as the fine brown hairs begin to develop in and around the ear canal, you should begin to pluck them, taking great care not to pluck too much (only a few hairs) at a time until the puppy becomes used to the procedure. A final aspect of hygiene that should not be overlooked is that of the teeth, which should be regularly cleaned to avoid the development and build up of tartar.