I use two different options depending on my dogs mood. If hes in the play mode I grab his fav. squeak toy. Squeak it once to get his attention and tell him what I want him to do. I use this during the day.
Another option I use is treats. Sometimes its just kibble other times its greenbeans or apple chips. He really likes all of them. But if im going to be working over and over to teach him a new trick I use kibble. I tend to use this option before his dinner feeding. I work from what I would feed him for dinner. That way he's not over eating.
The key to training is finding the one thing that drives your dog.
On a side note with our new puppy my older dog felt left out of the treat process so shes learning even more tricks like lay down and roll over and dancing. So even old dogs can learn new things.