Put the training leash and collar on the dog, reward it with some delicious food in your pocket, shorten the leash and pull it, say "sit", gently press its hind feet with your hands, until it reaches the correct position. Repeat "sit", and then make it sit still. After it sits, take your hand away and repeat: "Don't move", "Don't move", and be sure to stabilize it.
If it wants to stand up, press it back to its original position and repeat "sit" until it sits down again. Then say "Don't move" and slowly take your hand away. When he holds his position for nine seconds without your hand holding him down, say "Okay!" happily. Pull it to follow, give it a rewarding petting, and let it feel that doing so will be liked by the owner.
Repeat this training process, usually using ten minutes of training time, teach it several times a day, and move away from it when it continues to remain still.
When your dog has sat on the ground obediently, you can slowly leave the dog, that is, loosen the leash (before, you should have shortened the leash and pulled it). In this process, you should first place the dog leash on the ground, and then when you reach one end of the dog leash, repeat the command "Don't move". This will let the dog know that you are going to let it sit there to rest and stop moving.
Stretch your hands straight in front of you, do not bend your elbows but extend them gently. Use your pointer and wrist to indicate, flicking your fingers downwards without closing your palms. The "don't move" gesture is as follows: first stretch out your hand, slightly concave toward its nose, pinch it and release it, and put your hand on it for a while.