I use delayed reinforcement of a vocal reward as it works at any time whether you are training or simply on a walk or reinforcing social behaviors at home. Use a unique behavior cue for each desired action, and when the action occurs provide a unique short reward word "Haihai" "goodog" or equivalent. Think "Good Dog" whatever reward cue you use, dogs do read your mind. After several cue, action, "goodog" successes take a break and provide a favorite treat after cue and goodog without the action. Try different ones. Hesh will let you know quickly which treat is the right one. For Peter it is 1/6 of a 1/8" turkey (not beef) hot dog slice. He refuses commercial treats. Some trainers use a clicker, but his partner's voice is a better reward. Professional dogs like bomb sniffers etc. are active dogs and a retrieve is the reward. If you prefer treat reinforcement substitute treat for verbal reward.
Social training is next how to meet and greet visitors. I like the natural barking at intruders but once the doorbell rings or the door opens the "park" command is after training to retire to herm mat, stay, and be quiet. This has several good points. Hesh is removed immediately from over-friendly or frightened visitors until they are seated and non-threatening. Then hesh is released with a "greet" cue to smell the feet of the visitors. New over-friendly or frightened visitors are told to ignore this natural behavior until the dog gets acquainted. If the dog is social hesh will then approach an available hand in a friendly manner. If the dog is not so social hesh will normally assume a guard position between the guests and the door. A dog friendly approach is normally tolerated by any dog if the visitor is so inclined. Amusing note, Peter is rewarded at times long after a series of visitors have come and gone with three treats, one for "bark", one for "park" and one for "greet" as I am the trainer and may not be at home or busy away from the treats. He can count up to five visitors, and will expect three treats for each whether or not any cues or goodogs were needed.
The usual behavior cues can also be trained similarly "freeze," "heel," "wait," and "leaveit" on walks or in the backyard, with the treats after the training session is over. My rule is one treat for each cue no matter how many goodogs happen in the session. Again, "cue," "goodog," then treat.
For meds e.g. eye meds, "Look" then "EyesUp" move your hand slightly up when hesh follows it with open eyes and stays fixated on it "goodog." After that becomes a game add the eye meds, with an immediate goodog and treat. He will start begging for eye meds. Similar with any meds, a cue to present the affected area following a hand movement and be still.
A note on housebreaking puppies. I use the same procedure, and have either paper trained or outside trained several puppies in less than a day by the simple procedure of devoting as much of the day as necessary to moving the dog to the proper place each time hesh wakes, eats, drinks, or starts to sniff around, with a goodog for each elimination. Again the treat is delayed until the dog has moved back inside, then "goodog" and treat.