Clicker training is the best way to train a dog using positive reinforcement. With clicker training you can train your dog quickly, reliably, and in a way that is enjoyable for both of you. Dogs can learn a variety of tricks using the clicker, from a simple "sit" to elaborate performance tricks. With this training method, you can isolate any behavior in your dog and "mark" it with the sound of the clicker, making it much easier for your dog to understand exactly what you are asking of him. Once he understands the basic command, you can use the clicker to fine-tune his behavior so that you get exactly the right behavior from him. Because he understands exactly what you want, your dog will be much more likely to retain this knowledge long-term and can be excellently trained in quite a short time. It is important to remember that each training session should last only 15 minutes, but you can have multiple training sessions in a day.
1. Buy a clicker and treats.
You can find a clicker at any pet supply store, but no clicker is complete without a pocketful of highly motivating treats. If your dog isn't picky, you can just scoop a cup of his dry kibble into a pocket or baggy, feeding him that much less at mealtime (you can even provide all his meals via training if you wish.) If dry kibble doesn't interest him, you should invest in some highly scented and flavorful treats. One cheap idea is to buy hot dogs, chop them into pea-sized pieces, and microwave them until they are very hard and crunchy. The smell of this treat alone will motivate many dogs. Dogs also love dried liver (available at pet supply stores), or fresh cooked poultry.
2. "Load" the clicker.
Leash your dog and secure him somewhere. If you are indoors you can slip the loop of his leash over a doorknob, slide the leash under the door, and then attach it to your dog's collar after the door is closed. This way the leash is tightly attached to the other side of the door and your dog can't pull his leash free. When he catches on to the fact that you have delicious treats, he will try to lunge closer to you. Wherever you decide to leash him, it's important that his leash be very firmly secured so he can't quite reach you. Move to just outside his reach, and make sure his attention is on you. You can do this by calling his name or showing him a treat. Hold the treat in one hand and the clicker in the other. Then, click the clicker and immediately give him a treat. You are teaching him that the sound of the clicker equals success, and a treat is soon to follow. Be careful to always give him a treat once you've clicked, even if it's an accident. You will want to click-and-treat a few dozen times to drive this lesson home. You can vary the time between the click and the treat (don't always have the treat ready in your hand, or he will learn to only obey when you have a treat visible. Instead, occasionally click and then reach in your pocket for the treat.)
3. Click for the behavior you like.
For most dogs, this first trick will be "sit." Stand in front of your dog, treat in hand, and wait. You can move the treat upward in front of him (out of his reach) so that he points his nose up. In most dogs this will cause him to naturally sit, since he wants to watch the treat but his leash is too taut for him to jump for it. Doing this and shuffling slightly closer to him will usually prompt a sit. You can also just wait until he gets bored, at which point he will probably also sit. When he does plant his rear end on the ground, immediately click-and-treat. He will be confused as to why he got the treat. Then you must patiently wait again, or repeat your hand motion. When he sits again, immediately click-and-treat. Do this over and over again. After a few repetitions he will catch on, and he will sit on purpose so that you will give him the treat. (If he won't get to his feet because he's caught on a little too well, turn and walk away from him a few steps. He should stand up again so you can put him in a sit again.) At this point, your dog is trained. Start naming his behavior for him. Turn to him, move your hand in an upward motion (without a treat in it this time!) and say, "sit!" He's learned to sit for the treat, so he should sit right away. Click-and-treat. Continue this until he will sit based only on hearing your command. It's helpful to encourage him with a "good sit!" where you name his behavior with a positive tone of voice. If you want, you can also teach him a release word such as "okay!" or "release!" when you want him to come out of his sit. You do not need to click-and-treat for your release word.
4. Move on to a new behavior, and repeat!
From a "sit" you can easily teach your dog to "stand," to "stay," and "lie down." Most trainers like to pair each command with a hand signal. To teach "stand," raise your hand palm-up toward the ceiling as you step backwards away from your sitting dog. When he stand up to see where you're going, click-and-treat. You can add the verbal command "stand" once he seems to understand the hand signal and is reliably obeying. Put him through a "stand" "sit" "stand" "sit" routine.
For a "stay," put your dog in a sit, then count to five in your head before you click-and-treat. If he stands, make a negative sound such as "eh-eh" or "tsst!" Put him back in the sit and try again. When he obeys, up your count to ten, fifteen, and so on. When he is sitting until you release him with a word like "okay!" or "release!" you can begin verbally commanding him. Put your palm out toward him like you are pushing him and say, "stay!" then make your count, click-and-treat, praise, and release. Put him through a routine where he sit-stays and then stand-stays.
For a "lie down," make sure his leash is taut! With a treat in your hand, crouch down and hide the treat under your cupped hand just within his reach. He should slobber, lick, and try to steal the treat away. Given enough unsuccessful time, he will take the more natural position of lying down so that he can more comfortably sniff and lick. When his elbows hit the ground, click-and-treat. Repeat until he understands, then command him to "lie down." After a few repetitions of this, remove the treat from your hand. Use your hand as if it contains a treat, but instead click and then go to your pocket for the treat. Eventually moving your hand downward with your palm toward the floor will be the hand signal for this behavior.
5. Fine-tune and experiment.
Once your dog understands the clicker, you don't have to settle for his second best. Don't click until he's sitting the way you want, upright and pretty, or lying the way you want, like a dignified sphinx. If you click only on the perfect behavior, he'll soon learn what works and what doesn't. And experiment! Teach him not to jump up by clicking when he greets you with four paws on the ground! Teach him to "speak," to "shake hands," to "heel," to "roll over," and even to "limp!" Any behavior you like, catch him in the act and click-and-treat. You can eventually phase out the clicker as he responds to verbal and hand commands, but remember never to click unless there is a treat coming. In this way he will always perk up his ears at the sound of the click, and both of you will enjoy the process of teaching him what you expect of him.