How do I control my very playful dog?

Professional trainer or obedience school.

Exercise. You do not mention the breed so it is hard to offer specifics, but in general puppies and certain breeds need LOTS of exercise to burn off their energy. Try two 30 mins walks a day and see if that does not dial your pup down a notch or two.

If the dog is playing and bites you, you should make a sudden, high pitched, over-exaggerated yelp of pain, like a dog would do if it was hurt. Then, turn your body away from him.

You must be consistent in this. Every time he nips, yelp and turn away. He has to calibrate his bite, and his instinct is to calibrate based on other dogs. Your skin is softer than a dog’s so he must be trained to not harm you.

Dogs don’t cry, so crying won’t help. Hitting him in the face will not help.

Yes, he’s barking when you ignore him because he wants your attention. If you give him attention when he barks at you, he then learns that barking gets your attention, and he will continue to bark whenever he desires that attention.

What breed/x is he? how much focused exercise does he get every day? what training have you done with him so far?

You can try to buy this pet corrector. My daughter got me this for my dog who liked to chew on wood when we first got her. It just blows air in their face. They don’t like it. Her dog had a bunch of behavioral problems and this helped her a lot. It startles them and they snap out of whatever they were doing. It’s also great to take to a doggy park if ever a dog attacks your dog. This is a great way to break up a dog fight. She’s used it at the doggy park for some big dogs and they run away.

Your dog is a pup so it’s going to take time for it to settle down. In the mean time. Never try to train your dog when it is playful. They will not listen.
Before training, take your pup out for a long walk or play fetch. Once they are tired then work on training.
Only give treats for when they do what they are told. Start small. Start with stay. You will have to repeat this a lot. It may take your dog a few days to get it. Walk away a few feet and then call them to come. Don’t forget the treats.
With time they will get training time and that you are trying to get them to listen and respond to get a treat. Don’t expect it to work overnight.
Never give them a treat if they did it wrong because they are getting a mixed message and never get mad. If they get it wrong a lot one day, move on and try again later.
Another one is paw. Hide a treat in one hand and have them paw the hand with the treat.
Make sure they have their eyes on you at all time. If your pup is looking away, he will not learn to recognize your body cues.

Repeat the same individual movement for each new command word.
For sit I scoop the air in front of my dog.
For lay down I make a fist with my knuckles facing the floor.
For stand up on hind legs I flick my fingers up. All while saying the command.
There are also tutorials on youtube.

Yes, sounds like you need an obedience trainer and maybe more exercise for him/her as well.
As others have mentioned, breed and individual temperament plays a large part in dog behavior, and certain breeds are more stubborn, assertive/aggressive, dominant and hard to train.
There are a lot of low cost obedience classes available through local parks and recreation summer classes and I would highly suggest you get him into a class. If you do not make every effort to gain control of this dog the odds are good that you may end up getting rid of him and if you do, you are passing on his problems to others and possibly giving him a death sentence.

Not many people want to adopt dogs with behavioral issues. It is your responsibility to do your best to fix this problem with a professional.

Seek professional help; find a reputable trainer in your area and sign up for classes.

It sounds like your dog is overly excited, and hasn’t learned how to channel his arousal. @Seek‘s advice is great, but it does not work for all dogs. Scolding and hitting (“tapping”) his mouth will not calm him down, so that is a really bad idea.

I’m a dog trainer, and I have almost 20 adolescent dogs in my classes at the moment. I’d say that 70% of them have been through the same issue – this is very common. One way to really get rid of it: Teach a solid default behavior.

A default behavior is one that has been reinforced so often it just happens, without the dog having to think.about it. Usually, my clients choose a down. Thing is, you don’t tell the dog to lie down. For a full week, you only feed for spontaneous downs. Dogs catch on to this really quickly. Once your dog is downing often throughout the day, you start playing. Slow games, always with toys to bite (instead of hands). Remove the toy for a second, immediately resume play as soon as he thinks to lie down. This may take a while. Gradually, you can wait for downs in ever more arousing situations. Don’t ask for them, just pause what you’re doing and wait. Your dog is learning that being overly aroused will stop play, but lying down will make it start up again. He’s learning to channel his energy, and he’ll be a much safer dog to play with.

BTW, is your dog fixed? Fixed male dogs tend to be a less aggressive.

@Pandora Only when the aggression is connected to sexual impulses. I doubt this is the case here, and nine months would be very young to have a dog fixed. In fact, I’d recommend waiting for full maturity. Castrating dogs can make them less confident than they would be as intact males, and insecurity is root of a bunch of problems, many of them arguably worse than the OP’s issues.

@throwaccount I forgot to respond to the Maya thing. For harsh biting during play, the thing which I’ve found to work best is a solid recall, and using that whenever any of the dogs playing seem unhappy/scared/annoyed. Frequent breaks make friendly play.

Yes, and neutering/spaying for sure. especially neutering males, not only for the reproductive side of things but for a calming effect on behavior.

^ I’m going to caution against neutering again. Whether a dog is better off getting fixed is dependent on many aspects, and it should be discussed with a vet and trainer who know the dog in question. I’ve seen this idea go very wrong very often.