Dog training should just be one of the things that you do in a particular day. In other words, do not do it for all the time that you spend with your dog.
Play with him whenever you can, so that he can feel that being with you is not just all about learning new things, but having fun as well.
Train your dog in a place free from distractions
You have to take note that dogs can get easily distracted. In other words, if you want his full attention on the trick or task that you need him to perform.
Then you should make sure that you are doing it in a place free from distractions. Keep in mind that your other pets can distract him, as well as other people in your household.