It helps to be consistent so that it's clear to the dog what you want him to do. Ideally, all humans in the household should have the same rules about behaviour, such as jumping on furniture. It also helps if you always use the same commands. The most powerful tool you have for training a dog is positive reinforcement, so that the dog wants to do what you want him to do. It means that he associates the behaviour you want to elicit with pleasant experiences and feeling good.
Attention is one way of rewarding dogs.
They like to be praised, and they get to understand the words 'good dog' because they're associated with cuddles and titbits. Games can be used to reward dogs. They can be taught that 'sit' in a ball game means that they'll get to chase the ball, whereas if they leap up and down manically, you won't throw it. If you're consistent, and always make them sit, they'll sit automatically. Titbits are useful as rewards, and as lures, to attract and keep your dog's interest.