Help him relax when he comes home. When your puppy gets home, give him a warm hot water bottle and put a ticking clock near his sleeping area. This imitates the heat and heartbeat of his litter mates and will soothe him in his new environment. This may be even more important for a new dog from a busy, loud shelter who's had a rough time early on. Whatever you can do to help him get comfortable in his new home will be good for both of you.
The Boxer is happy, friendly, intelligent, attentive, and loyal. Boxers develop strong, close bonds with family. They have lots of energy and a serious demeanor, though they can be clownish and playful as well. They like to grab and carry around just about anything they can in their mouths. Boxers tend to get rowdy when the food bowl is empty. They make excellent guardians and companions.
The first method is called capturing. Stand in front of your puppy holding some of his dog food or treats. Wait for him to sit – say “yes” and give him a treat. Then step backwards or sideways to encourage him to stand and wait for him to sit. Give another treat as soon as they sit. After a few repetitions, you can begin saying “sit” right as he begins to sit.