If you make training fun both you and your dog are going to want to do it. The opposite is true too. If you turn training into a chore, it probably isn't going to be all that enjoyable for all parties involved. Below is a video of a training session that I did with my dog V. In it I am using a ball as his reward. (This will work for a lot of dogs.) You can use food for this, or different types of toys.
During your training sessions you'll want to practice all the skills your dog knows. Once he is doing well at certain things, make him do those things for longer. You can also practice creating more distance between you and him while he is maintaining what you're asking.