When first training your Yorkie to "heel" and walk nicely beside you, it is highly recommended to use a well fitting harness for small toy breeds.
Many owners complain of "the dog walking them". This does not need to be the case. By taking time to make sure that your Yorkie understands the meaning of "Heel" and with consistent training, you can enjoy nice walks where your dog actually strides right to the side of you.
When you set out for your walk, have your Yorkie to your left side and keep the leash short; with only enough length for him to be by your side and not able to walk ahead. Be sure to give the command word of "Heel" as you begin to walk. If at any time your dog tries to walk in a different direction, do not stop but continue walking where you want to, at a very slow pace. If your Yorkie stops, again do not stop, but continue walking at a slow pace. When you have your Yorkie on a harness, as explained above, continuing to slowly walk will not cause injury.
At any time when your Yorkie is striding nicely beside you, say the command word of "Heel" to reaffirm that your puppy
is indeed heeling and offer words of praise. With the tone of your voice, you must convey that he or she is doing something truly great.
If for some reason you choose to not use a harness, if your dog walks or runs ahead of you, do not stop and jerk on the leash. That type of training is not for toy breed dogs.
If your Yorkie gets ahead of you at all, steadily slow down. If your Yorkie still
tries to get ahead of you, slow to a stop and then reverse directions. This shows your dog that any time he tries to run ahead, all he will find is that he will not reach his target and will instead have to go in the opposite direction. Once your dog walks nicely beside you, reward him by reversing again in the original direction.
When your walk is complete, if your Yorkie has correctly heeled the majority of the time, give a wonderful treat at the end of the walk. Do not give any treats if your dog was all over the map! With a bit of time, both of you will greatly look forward to walks together.