Choosing the right dog trainer for your dog is as important as the right babysitter for your kid.
In any case, your dog’s little mind absorbs everything. In that sense, it’s like a child, everything it experiences is downloaded into its subconscious, so you want to make sure you trust the person who is going to be programming your dog. For instance, some trainers train using fear; making your dog submissive, yet cowardly, and somewhat afraid of humans. Some people, don’t want this. Other trainers, use love and rewards, making your dog so joyful towards you that it wants to behave and listen.
The choice is yours!
Do you like their energy? Are they giving off loving vibes, or aggressive, assertive ones? Again, it’s completely up to you, but how this person is will shape the personality of your dog, that is important to note.
Also, what is their method of conditioning? Are they using negative conditioning, to where they are punished (yelled at, hit, ect) if they are bad, and not punished if they are good? Or are they using positive conditioning, to where they reward your dog if they are good, and the dog gets no reward if they are bad? Important to note, I once saw a dog trainer rewarding a dog with homemade ice cream, which sounds like and all, and I’m sure the dog loved it, but icec ream is not good for dogs, so maybe make sure they feed your dog appropriately.
Or perhaps, they are using both, negative and positive conditioning: punishing the dog when it is bad, and rewarding it when it is good (this seems to be the most productive method).
Other things to look out for might be whether or not the trainer has experience, if they seem to enjoy what they are doing, if they seem knowledgeable, and most importantly, how your dog reacts to them.
Again, I know it sounds like a small task, but choosing a dog trainer will have a lot of impact on your dog's life and personality.