To find the right motivation for your dog can be quite tricky, and you may have to change your tactics ever so often to keep your dogs attention at a level suited for the task ahead.
When starting to learn a new trick, or command, I prefer using treats and kind words. For me this works wonders with puppies. Puppies eats everything they come across and they are on a constant search for something new to taste. Treats get their attention, keeps them away from eating everything they shouldn’t and don’t work them up to much. I always have with me two, three different kind of treats in my pocket so I can take advantage of every opportunity presented to us. As soon as the dog understands the command/trick, I reduce the use of treats gradually until I stop all together.
Later on, when the dog gets older or he has learned the correct response I rather use a tennisball or any other kind of toy. The reason for not introdusing the tennis ball too early is simply because it works too good. Throw the ball once, and the puppy is all “ball”. You need to find a balance between the reward and the energy level you need your dog at to keep him focused on you. One thing I love about the ball is it gives me a chance to reward my dog instantly at greater distances. With a ball, or any kind of toy you should not let the dog play for more than a few seconds before taking it away from him and try again. Otherwise he will loose focus and get bored of the toy.
This works great for me and my way of training, but may not work at all for others. Learn to know your dog and find what work for you. Some dogs needs a lot of motivation to get started and then maybe the tennisball should be introduced from the beginning. Others are so high on energy that a gentle “good boy” is more than enough.
The clicker training is quite popular for time being, but I find it cold and it doesn’t help me build a relationship with my dog. I belive the reward, and response should be given directly from you to your dog. Use your voice to tell the dog he’s done good, give him a treat from your hand, make sure he knows the reward/response is coming from you. Later on his motivation should be to make you happy, not the treat, tennisball or a clicking sound.