Never leave a puppy in his crate all day; he needs several bathroom breaks, as well as play and feeding times. Even though he won’t want to soil his sleeping area, if he is in there for extremely long stretches, he just might. (He can’t help it!) And if he does, it is because his owner has neglected his responsibility, not because the dog has misbehaved.
Help him relax when he comes home. When your puppy gets home, give him a warm hot water bottle and put a ticking clock near his sleeping area. This imitates the heat and heartbeat of his litter mates and will soothe him in his new environment. This may be even more important for a new dog from a busy, loud shelter who's had a rough time early on. Whatever you can do to help him get comfortable in his new home will be good for both of you.
New puppy owners often make the mistake of endlessly worrying about finding the right accessories, puppy treats, or bed. They spend little or no time thinking about how or what they will teach their new puppy. Yes, a puppy needs nutritious food and a safe, warm place to live, but another equally powerful and important biological necessity is the need for a strong pack leader.
It typically takes 4-6 months for a puppy to be fully house trained, but some puppies may take up to a year. Size can be a predictor. For instance, smaller breeds have smaller bladders and higher metabolisms and require more frequent trips outside. Your puppy's previous living conditions are another predictor. You may find that you need to help your puppy break old habits in order to establish more desirable ones.