After I got schooled on the proper touch command (Roxy targets the palm of my hand with her muzzle), I started using targeting more and more to aid in her training.
We started out shaping that behavior; first looking at the object, mark/reward, then she had to move closer to the object for a mark/reward, and ultimately where she had to touch the object with her muzzle for a mark/reward.
We've progressed to her targeting other people's hands; it's how we introduce her to new people and it really helps keep the pressure off her. I've learned that most people can't be non-interactive with a dog, especially since Roxy will typically go right over to smell them. People's first instinct is to reach over her and pet her; Roxy's first instinct is to duck and back away when they do this.
So, I give people an active part in the game. Initially, I didn't want other people speaking to her or giving cues until I knew how she would do, so I would ask people to put their hand out, horizontally, next to their bodies, and ignore her. I started asking her to "Go say hi!" which is her cue to literally, go say hi to the person, and target their hand. She'd run over and touch their hand, and get a mark/treat from me. She's now at a point where other people can ask her for a touch, and she'll run to them to do it. Literally any adult can make this happen, whether they are giving the cue or I am, or whether I have the treats or they do.
So, we do this a few times, and then she's properly "introduced" to the person, and often she'll run over to them repeatedly, looking for additional mark/treats. After she's done it herself (without a cue) two or three times, the game is over and she will go over and stand next to the person, which is her invitation to be pet. It was really amazing to watch her figure this game out and then suddenly not be afraid of that person. Even if she's not interested in being pet by them, she's not afraid of them.
So, on to the video below. Roxy is the type of dog that doesn't like other dogs in her face, for the most part. Dogs that she's already "friends" with can be, but it just depends on the dog, really. She initially liked Sonny very much. She threw out all sorts of play bows and vocal invitations to play. But after his quarantine period, Roxy seemed less interested in him. And Sonny is a muzzle-licker. He'll be wandering by another dog, and just reach over and lick their face a few times, and keep on walking. Needless to say, Roxy is not a fan of this.
So I initially started capturing the behavior. Each time he approached her and licked, Roxy would get a mark/treat. She started looking for the face lick and anticipating the mark/treat. I moved on to teach her to target Sonny's muzzle with the cue "Where's the puppy?" so not only is she getting a mark/treat for Sonny approaching her, she's getting one for actively seeking him out, and specifically seeking out the muzzle-muzzle interaction. I used the word "puppy" instead of using Sonny's name because when we started this, Sonny wasn't comfortable hearing his name, so I wanted to keep the pressure off of him while still helping Roxy feel more comfortable around him.
She's now seeking him out and making attempts to target his muzzle. It's not a fix-all, but there are much fewer avoidance behaviors when Sonny approaches her face, and now we're getting NO snarling, whereas before, he'd lick her, and she'd lift her lip at him. She is also inviting him to play more often, and taking the initiative to jump into Sonny and Buster's play sessions. I keep them short and sweet and it's a lot of management on my end, to make sure no one is getting too amped up, but I'm really impressed with her progress.
Also notice Sonny approaching me in the video. It's his nighttime thing, as of late. He will come out of his crate and jump in the papasan chair in the background, and when Rob or I throw Buster's ball, Sonny will run after Buster and the ball. Last night, during the video, he was approaching me to see what sort of treats I had. I was using chicken chips, something I never considered high value before, but Sonny seems to be very interested in them, so I'll have to get some more since we polished off the last bag during Roxy's targeting session and Sonny's occasional approaching me session last night!