I am not a big fan of scoializing my dog with strange dogs (and do not recommend dog parks for a number of reasons).
My dog is part Akita, and is fairly aggressive to strange dogs if he is on a leash or smply let loose in a dog park environment. He is this way because of his genetics and his temperament. He is a very dominant dog and will not back down from confrontation - ever.
Having said this, I do let him socialize with a select few dogs I have interacted with and know to be temperamentally sound. There is a method I use to introduce my dog to a strange dog - and it works quite well.
I must give a few preliminary warnings, though, that may help to keep things in perspective. If you are going to introduce a fully grown male to another fully grown male or a fully grown female to another fully grown female - there will be a dominance scuffle so be prepared for that. If you would like an explanation of a dominance scuffle, feel free to email me. There is a big difference between a dog fight and a dominance scuffle and a trained eye can help to tell the difference. Also, if you are introducing two very dominant dogs, there will be a dominance scuffle. It is best not to socialize two very dominant dogs, especially if you are not completely sure that the other dog or your dog displays defensive aggression.
So, with what kind of dogs can I use this method? Female & male, adult & puppy, dominant & submissive. If you have any questions about this, please feel free to contact me.
Here is how the method works. If you are introducing your dog in another person's home, have the other dog owner hold the dog, or put the dog in a different room where the dog will not bark and get stressed. Remove all bones and toys (possible sources of conflict) from the floor and put them out of sight. Keep a leash on your dog. Let your dog sniff his new environment, for about five minutes. Put him in the other dog's crate. If your dog is too big for the other dog's crate, bring yours along and set it up. Then give your dog his command - go home - and crate him. Let him adjust to the crate for about one minute. Then bring the other dog over and put him in the same crate. Sit right out side the crate and praise both dogs extensively. They should be sniffing and inspecting each other. If one dog begins to growl, bang on the cage and say a stern NO! When he stops, praise and praise again. Keep them together in there for 5 minutes or so. The crate is an area that the dogs are naturally relaxed in and they don't have lots of room to go at it. And since you are right there in front of them, they are really itching to get out and so are pretty oblivious of eath other (except in the case of puppy and adult, the adult will most likely be oblivious to the puppy).
So when both dogs are quiet, open the crate and let them out to play. At this point, the dogs should be ok. There may be a small dominance scuffle, with growling, neck biting, and pacing, but it should be short and play should resume. Playful stances include tushies in the air with tails wagging and chasing behavior. Lots of barking too. But you know your dog best, if he seems at all uneasy or nervous, put him back in the crate to calm down for a while.
I recommend meeting the other dog first before introducing your dog to him, bring home his scent on your hands and praise him as he smells you. Again, I am not a big advocate on socializing your dog with other strange dogs, especially during the first year of his life (there are exceptions to this). If he was with his litter and mom for 8 weeks, he will know how to interact other dogs as an adult. You really want to avoid situations where your dog under one year shows submissive behavior to an aggressive dog, and that dog continues to attack on your dog even though he has submitted. Your dog will learn that submission does not work and his defensive drive will kick in. So use your good judgement when socializing your dog, know the temperaments of the dogs you will be letting him play with (after all, you wouldn't let you children play with other children you did not know, or knew to be mean bullies), and praise him for good behavior as much as you can. If you know your dog has shown dog aggression in the past, with the help of a professional, he may be able play with other dogs, but don't try to have a go at correcting this behavior on your own.