Instructions
Exercise your dog for at least an hour before your guest visits -- go jogging in the woods, down the street or at the dog park; play flying disk; go swimming or play other games your dog enjoys. The dog will release energy during these activities and be calmer during your guest's visit.
Correct bad behavior firmly as soon as your dog displays it. If it starts barking when it sees your friend, for example, correct it with a sharp "No!" or "Shh!" Dogs don't understand delayed punishments, for example refusing to take them on a car ride after growling at your friend. Dogs also respond poorly to yelling, screaming and hitting, which can permanently ruin your relationship with your pet. Immediate, firm, calm correction is necessary for your pet to get the message.
Communicate this correction strategy to your guest and encourage him to correct your dog the same way when necessary. This establishes you and your guest as the dog's leaders. Dogs respect and follow their leaders; the dog won't resent you or your guest for calm and assertive correction.
Reward the dog immediately for good behavior only. For example, if the dog stops barking and calmly lies down next to your guest, give him a treat or affection to reinforce his calm, friendly attitude. Better yet, have your guest give him the treat/affection. Rewarding the dog in an attempt to get him out of the way -- for example, throwing a treat to divert his attention away from your friend -- only reinforces bad behavior. If your guest caresses and talks sweetly to your pet in an attempt to stop his growling and barking, this also reinforces bad behavior. Communicate your reward strategy to your friend to avoid sending mixed messages.
Have the dog neutered. Neutered dogs are generally less aggressive and territorial.
How Can I Get My Dog to Like Someone?
Most owners consider their dogs a part of the family. When a dog barks excessively or acts aggressively toward a family friend, it creates an awkward situation for the owner. If you adopt a calm and assertive attitude, consistently reward your dog when appropriate and consistently correct your dog's bad behavior, your pet will act more positively toward your friend.