In order to motivate your dog you must provide things your dog likes as payment for doing what you ask. This is known as Positive Reinforcement. By providing this payment your dog is more likely to repeat those behaviors in the future. The easiest form of payment is small food rewards. Other things like toys, play, praise, and petting can be used as well depending on the situation and what is motivating the dog at the moment.
Kelly and I work with hundreds and hundreds of different people and their dogs each year. The people that have the most success with training their dogs are the ones that pay their dogs a hefty salary. The more payment you give, the more behavior you will receive.
When I first got into dog training I was a punishment based trainer. I really didn't give rewards at all. In fact, I "rewarded" the dog by not giving corrections. It's something I feel bad about to this day, but I can't change the past. Transitioning from no rewards to starting to use rewards consisted of me keeping a stick of string cheese in my pocket and slowly and frugally doling out the tiniest of rewards. Since then I've transitioned to wearing a treat pouch and doling out treats at a rate of reinforcement that I've only seen Kelly offer. Since I've started using this high rate of reinforcement I've noticed that the clients I work with our getting better results. (If they follow my lead.) A great example is the Reactive Dogs class we had last night. Cooper the pit bull keeps his eyes glued to his mom. He wasn't always like this. When we had him in Basic Manners 1 he was hard to handle. Last night in the final Reactive Dogs class he kept his eyes glued his mom and didn't even bat an eye at another dog. Why? Because Alexis pays Cooper a very high salary. (Everyone in the class did awesome, just Cooper really stuck out seeing his transformation.)
Paying a dog isn't bribery, it's the laws of learning. Animals, human or dog, repeat behaviors that provide good consequences. If a dog is paid for holding a down stay on a mat a few feet from the dinner table, he will most likely stay on that mat. This is a lot more effective and stress free than yelling at the dog to "go lie down" repeatedly. This is just one example.
Don't be stingy. Pay that dog. Find something your dog likes and use it as payment for the behaviors you like. If you want your dog to really respond to what you ask, don't pay him minimum wage, give him a six figure salary.