I took my dog to professional triainers. However, from what they taught us, I would suggest that you spend atleast one hour with your pet every day.. Take your dogs fav treats,a dn show them to him. dont give it unless he listens to what you want him to do. for example, if you want him to understand the command "sit", put your hand on his back, slowly press down, while continuously saying "sit". when he does finally sit on his haunches, then give him treat and praise him a lot. he shud understand the voice tone, the word,a dn what you want him to do. make sure you show your hand in front of his eyes, and in the way you want him to know it...open palm facing up,(tht way it comes under his chin) or open palm, facing down, just so that he can see it.
Our trainers here told us that dogs have limited vocabulary..of 100-150 words. so commands should be simple and short.
Anothet tip i would like to give all dog owners is tht, train ur dog in your native language as much as possible, instead of english. That way, they would not obey anyone else,a dn listen to you more. so chances of running away, or being lost are fewer.
all the best. hope the above reply helps.