Little Boy is responding well to all the basic commands - SIT, DOWN and STAND.
Obviously I use only reward-based training, and so I have a treat bag permanently attached to my belt so that I can reward wanted behaviours whenever they occur. It is very important to let young animals know what is a 'good' behaviour, and what is a 'bad' behaviour so continual and consistent guidance in the form of rewards for 'good' behaviours is very important. I do use voice, touch and games too, but with food-motivated dogs such as Labradors, treats make the whole process very simple.
It does carry its own problems in that I have to ensure that the treats do not make up a large proportion of the puppy's diet - a young, growing animal needs a well-balanced dog food suitable for his age and breed. Similarly, the older animals are prone to putting to weight, so the quality and volume of treats has to be strictly controlled.
For the puppy I am using a mixture of his kibble pellets and dehydrated liver cubes. The latter are available in little tubs from pet stores, have no additives or chemicals and come cut in to little cubes of about 0.5cm. They are quite soft so I can break them up further with my nails and so can treat frequently using the tiniest of pieces. The older dogs can have problems with sensitivity to wheat so for them I use gluten-free beef or chicken chomping chews. These are made from 50% meat, and are soft, thin flat strips about 15cm long x 2cm wide. As with the pup, I break the strips in to about 4 pieces to have in my treat bag, and reward with a small piece broken off one of these quarters. The size of reward can thus be varied as appropriate for larger or smaller dogs.
If your dog is very overweight you can measure out the dog's daily kibble allowance, and instead of feeding it all at one time in the dog's regular meal, you can put half of it in your treat bag and use that to reward behaviours. If your dog is fully grown but is very stubborn, you could try not feeding a meal at all and instead put the dog's daily kibble allowance in your treat bag and reward desired behaviours constantly during the day so that he has to work for every piece of kibble. However, if you try this approach you would need to be careful that you were consistent and fair in your rewarding, and that your dog was an adult, in good health, and no longer growing as puppies need a different feeding regime to adult dogs.
For the older dogs, if I am trying to teach them something new or difficult, or trying to encourage them to do something they are worried about - such as getting Little Girl to do the Dog Walk at Agility - then I will use small amounts of a high-value treat. High-value treats are exactly what they sound - a treat that is of high-value to your dog. It could be a piece of cheese, or fish, cream, a piece of hot-dog sausage - whatever your dog adores and will do anything for. Obviously, to keep their status as 'high-value' you must limit their use to those occasions when you are having problems otherwise they will lose their value. You can also use them to distract your dog when working on resolving behavioural issues such as inappropriate barking.