Discourage him from biting or nipping. Instead of scolding him, a great way to put off your mouthy canine is to pretend that you're in great pain when he's biting or nipping you. He'll be so surprised he's likely to stop immediately. If this doesn't work, try trading a chew toy for your hand or pant leg. The swap trick also works when he's into your favorite shoes. He'll prefer a toy or bone anyway. If all else fails, break up the biting behavior, and then just ignore him.
It's important with all dog training but especially with young puppies to use lots of encouragement, praise and rewards (positive reinforcement) in your training. Start your puppy training sessions as soon as your little puppy arrives at your home - it's never too early. Set your puppy up to succeed, concentrate on developing desirable habits in your puppy and preventing undesirable behavior. It's much a better alternative to put your puppy on the right path from the start, rather than trying to correct established problem behaviors later on.
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.