practice, practice, practice. Play with other and better players. Pay attention to how certain shots perform, and try different shots in different rough %. Read the tutorials to the right, the putting and chip/pitch tips are excellent. Practice mode allows 10 shots per hole, use them. Dont be so eager to make Master in 1 week, it gets harder and you need to learn the right shots for each scenario.
If you got a couple of bucks, equipment upgrades can make the game more enjoyable and make you more competittive.
Play match play, play every course and record your scores.