Confidence-building might involve temporarily withholding toys or treats from the pup, temporarily hugging or restraining the pup, making strange noises, or temporarily making mildly scary faces or slightly weird body movements, and then praising the pup and offering a food treat. The food reward builds the puppy's confidence by reinforcing his acceptance of your scary faces and weird actions. With each repetition you may act a little scarier and weirder before offering a treat. After time, your puppy will confidently accept any human action or mannerism. If the puppy ever refuses a treat, you have stressed it. So stop being silly for a while until you have handed the pup half a dozen treats in a nonthreatening situation.
Puppies have to be trained to enjoy teasing. For example, being relentlessly pursued by a child with outstretched arms can be the scariest thing on the planet for a puppy without prior preparation. However, being pursued around the dining room table by an owner doing monster-walks can be one of the most enjoyable games for a puppy who has been taught to enjoy playing the game. Most dogs love to be chased as long as they have been taught that the game is nonthreatening.
Malicious teasing on the hand (taking pleasure in the puppy's displeasure) is just too cruel and silly for words. It is decidedly not funny to cause the puppy discomfort or to make him afraid. You are teaching the pup to distrust people, and it is your fault when, as an adult, the dog reacts defensively. Sadly though, it will be the dog who gets into trouble, not you. Please don't allow this to happen.
There is a simple test to determine whether or not the puppy finds teasing to be enjoyable. Stop the game, back up, and ask the puppy to come and sit. If the puppy comes promptly with a wagging tail and sits with his head held high, he is probably enjoying the game as much as you are. You may continue playing. If the pup approaches with a wiggly body, lowered head and tail, makes excessive licking motions with his tongue, and lies down or rolls over when asked to sit, you have pushed the puppy too far and he no longer trusts you.
