Like young children, sometimes puppies just can't help themselves. The world is just so... exciting! A playful pup can get out of control, however, knocking down kids, jumping on guests and nipping at your hands and ankles. This behavior is not his fault, he just needs to learn when it is and isn't acceptable to release his excess energy.
Settle or Sit Command
A young pup's attention span might make it hard for him to learn complex commands, but by the time he's six to eight weeks old he is capable of learning to either "sit" or "settle" on command. Either one is a helpful tool in calming your puppy down when he gets overexcited, and both are basic commands you can use with him throughout his adult life if you need immediate control. Choose one to teach your puppy and work with him consistently every day. Each time he starts to get too excited, and before he's completely overwrought if possible, tell him to "sit" or "settle" and calmly praise or reward him when he complies.
Cold Shoulder
A hyper puppy wants your attention and will do nearly anything to get it. He may not realize that you are scolding him, or are unhappy with his behavior, only that he was successful in getting what he wanted. To teach him that out-of-control excitement isn't the right answer, ignore him when he gets too enthusiastic and give him attention as soon as he settles down. Remember to speak and pet him calmly when he is relaxed so that he doesn't get worked up again.
Exercise
Regular exercise burns off some of your puppy's excess energy and provides important bonding time with you. He will learn that during play time it is appropriate to run, jump and generally act like a silly puppy. After play time, however, show him that it is time to relax by holding him close and gently scratching his head and belly. Time spent together will also help reduce his excitement when he first comes back inside since he won't have spent so much time alone.
Crate
If your puppy is especially out of control, or if you need an immediate solution, putting him in his crate for a few minutes can calm him down. Don't use the crate as a punishment, but more as a place to cool down. When your puppy is calm, let him come out of the crate if he wishes and give him some gentle attention so he knows that calming down was the right answer. Don't, however, let him out when he is crying or howling to be released or you will teach him that making noise is a good way to get your attention and get what he wants.