So, I am 6’5" and 250#. This is what works for me. You will most likely not want to do the same if you are smaller or more timid.
The ZipperJJ voice thing can work if the dogs are not hard into each other, and is worth a try regardless.
First off, it is serious business. I won’t punch or kick a dog needlessly, but if I am breaking up a real dog fight, I am not going to be gentle, feelings of the owner(s) be damned, and if the dog goes for me, then there is no notion of fair fight.
First off, be paying attention to the dogs. Learn to read body language and know who is looking for a fight. Learn what situations intimidate your dog. A scared dog is a fight waiting to happen. Know who was looking for the fight, and who got jumped. Not just to be fair, but pulling the “he started it” dog out may be enough to end the fight, though once the fight is on, the good guy may not back off, so be ready for that. Also, it is not uncommon for the asshole dogs to be getting their ass kicked by the time you get there, so you may need to manhandle the good guy…I may be a little more gentle in such case.
If you didn’t see it start, make no assumptions about who started it. Grab the dog you most safely handle and remove them from the fight as quickly as possible.
If big dogs are seriously into it, I may try to grab for the end without the teeth and lift/throw/flip them forward. When their back legs are suddenly taken from under them most dogs back off. If I grab collar or neck skin, I also pull them up off the ground. Loosing footing disorients the dogs, and limits their options. I will usually try to literally throw the dogs away from me and away from the fight scene.
For less serious scuffles I grab for the scruff of the neck and collar if there is one, and grab hard. Unless the dog has seriously loose skin, it is very hard for them to get their teeth on you. If you see the teeth coming, and cant get out of the way, use knees and elbows or at least make a fist. Smaller dogs can’t get their mouth around a closed fist, and bigger dogs will have less leverage with their mouth farther open.
It really, really helps if you have had a big dog that likes to roughhouse. Most dog moves are instinctive, and with practice, you can see them coming.
That goes for the dog too. Dogs need to learn to roughhouse at a friendly/fun level without panic. Usually it is the dog that is intimidated that turns the fun into a fight, not the dog who is being an asshole.
To this end, I much prefer to let the dogs work out minor tiffs on their own, and I think this where many people I see at the dog park error. Dogs need to work out the pecking order, and if the people try to change that it just causes trouble.
Many dogs will back off when the the other dog yips, IF it was play to start with. You can teach this to your dog if you roughhouse with it. If it nips you a little too hard, let out a loud yelp and stop the play immediately. A few times of this, and the dog will learn that the fun ends if they nip too hard. Other dogs, this seems to turn on their prey instinct. It is a good sign if the dog backs off when the other dog yelps…they want to play, not fight.