One word: Practice!
If your dog is not very good at something or some things, the answer is practicing until your dog gets better.
Before you start, check to make sure your techniques are solid. You have to be patient with yourself as well as your dog. Set up situations, that will make it easier for you and your dog, such as using high value rewards. Associate something that your dog loves with the behavior you are practicing, like play, praise, petting or food.
The right motivation is powerful and then set up drills and repeat, repeat, repeat.
Longoriahaus Dog Training is a dog training service in the Kingwood, Humble and Houston, Texas area. Longoriahaus Dog Training can help you raise a happy and reliable dog.