Write an article based on this "Look for and reward natural sitting behavior. Begin issuing the “sit” command. Reinforce sitting behavior with a clicker. Train your dog to sit or stay when the door is open. Be patient when training your dog. Keep your dog focused."

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If you walk into a room and your dog sits, then your job is half done.  Reward your dog when it sits, even if you don’t issue the command to sit.  Give your dog a treat when it sits in front of you. After a few days of rewarding the dog for sitting naturally, begin issuing the “sit” command before giving a treat.  Get on the dog’s level and hold a doggie treat enclosed in your hand a few inches from his nose.  Bring it up and toward him slowly.  Your dog will lower itself back onto its butt.  When its butt hits the floor, reward your dog with a treat. A clicker is a small device which makes a clicking sound when pressed. Click  when your dog sits (when his butt hits the ground). The clicker tells the dog he has completed the behavior you asked for correctly. Reward about five seconds after you clicked. This will allow the dog to make the connection between the click and the reward, but not with the motion of your hand toward the treat or another movement. The dog will quickly learn that the clicker sound means he has completed a behavior correctly, and can expect a reward.  If your dog has already been trained with the clicker to engage in a different behavior, you might confuse the dog if you try to retrain it to sit instead of engage in its original behavior. If the door is open, or about to be opened, getting your dog to remain seated can be a challenge.  Incorporate an open-door phase into your training sessions.  Teach your dog to stay seated as you back away towards the door.  Put your dog far away from (but within eyesight of) the door.  If your dog starts moving after being seated, put your hand up and say sharply “Stop!”  Re-seat your dog in its original spot and repeat the exercise. If your dog has difficulty remaining seated, get a friend to help your dog stay seated while you can open and close the door. When your dog is able to remain seated despite you opening and closing the door, give it a treat (even if it took help to keep him stationary).  Get in the habit of giving your dog a treat each time it is able to remain seated when the door opens. To prevent your dog from running out when you come home, repeat this exercise but enlist aid from a helper who opens the door from the outside.  This way, your dog will know to stay seated when you come in. Practice for 10-15 minutes in at least three different sessions each day for about two weeks.  Different dogs learn at different rates.  Do not be discouraged if your dog seems to be slow to learn how sitting works.  On the other hand, do not be quick to assume that your dog has mastered sitting just because in one session he or she seemed to sit with every command during that session.  Stick with it and stay positive.  Your dog will eventually learn to sit. Like people, dogs can’t stay focused for periods which are excessively long.  If your dog loses interest during the training session, your training may have gone on for too long.  Let your dog go out before you begin the training so that he won’t have to relieve himself during the training.  Do not train your dog in the presence of guests or other distractions. Issue the command to sit every time you or someone in the house opens the door. Give your dog a treat when it sits. Even after training, keep an eye on your dog.  Sometimes the excitement of an open door or a new person can inspire him or her to dash outside.  When entering your home, open the door slowly and come in quickly, staying alert for potential dog movement.