This is a basic action to teach your dog.
This is very easy to learn because it is natural to the dog and is easily performed.
“Down” is a very important action that puts the dog into a passive state.
1) It is very important that your dog knows to sit in command before he learns to lie down.
If not, there is a guide that explains how to teach your dog to sit in command: https://www.youtube.com/watch?v=5-MA-rGbt9k.
2) Bring your dog into a quiet room with food that he loves in your hand and pocket (you will repeat the actions several times).
3) Tell the dog to sit and give him treat / food while sitting as a reward.
Tell him “good dog”.
4) Put extra food in your hand.
When your dog sits, show him the food in your hand and put your hand between his front legs.
The dog’s natural response will be to follow your hand with his nose.
Lower your hand toward the floor and when the dog bend the front part of his body say: “Down” , Give him the food and praise him.
*If he does not bend with the entire body into a the position, help him with a slight pressure on his back.
5) Repeat the operation several times.
After the dog seems to understand the action, try to do so without putting the Food between his legs, and only to direct him with food from far.
When he does, give him the food and praise him.
After further training try to do this without any treat.
6) It is important that after the dog seems to understand, try to tell him “Down” without a reward, and after performing it praise him with caresses and good words.