The Jumping Dog
One of the most common complaints I hear from clients is "my dog jumps on me and everyone else." While some people think this is cute (as long as the dog isn't muddy or big enough to knock them over), it doesn't mean the dog loves you and is showing that and it's definitely not behavior you want to encourage. Fortunately, it's behavior that's fairly easy to correct.
You need to help your dog replace the insecure, excited, impulsive jumping behavior with a calm controlled behavior. If you TELL him to sit or down, he's not controlling himself, he's relying on being told what to do, and when he's really excited he may not even hear you. Instead, arm yourself with a toy or a treat before you walk into the house. When the dog comes at you, stand your ground and calmly show him what you have in your hand. If he jumps for it, just move your hand back. Don't say anything. He will see this doesn't work and he will start to think about other options. Just stay calm and quiet, and before you know it your dog will put himself in a sit. Mark that by saying "yes!" and hand him the treat. When he is giving you this behavior right away all the time, you can raise the bar by waiting for him to do something else, like go into a down or move farther away you and give you more space.
If a dog catches you by surprise and you don't have a toy or treat, cross your hands over your chest and look away from the dog. Don't spin around. That just adds more energy to what's happening and can invite him to jump on your fro behind. Just give him nothing. Once he drops back to the floor, count slowly to 5, then acknowledge the dog with pets and praise. You'll be reinforcing the four-on-the-floor behavior instead of the jumping.
Another exercise you can do is to put your dog on leash and tether the leash to something, like a fence or a heavy piece of furniture. Approach the dog (or have a friend approach if he likes to meet new people and gets excited about it). If he stays calm with all four paws on the floor, see if he'll give you a spontaneous sit. Either way, praise him, pet him, and give him a treat. If he starts jumping, back up so you're just out of range. Just stand there. Don't talk to him, look at him, or engage in any way. When he has all four paws on the floor (or sits), praise him and step forward. If he starts jumping, immediately step back. If he keeps all four on the floor, pet, praise and a treat. You can do this exercise with him throughout the day (releasing him from his tether in between), but don't do it for more than 5 minutes at a time. You don't want him to get bored or frustrated. Just be sure to end with the good behavior each time, even if you only do the exercise once.
If you have a dog who is really hyper and crazy and can't calm down, you need to redirect that energy. Rope toys are great for this. Get a big sturdy one and hold it up until the dog sits. if he tries to grab it just calmly move it back out of reach. Once he's sitting say "yes!" and then ask him to take it. When he grabs it, give him 30 seconds or so of good tugging and then put a treat by his nose and ask him to "give". When he lets go for the treat say "yes" and give him the treat. Then show him the rope and do it again. Now he's getting to work off some of that energy and learn to focus and contain it to get what he wants.