I'm just talking from personal experience but I was a three sport athlete in high school picked up golf the summer after I graduated and was an 11 when done. I played soccer and tried out for the golf team and made it. I got to a 4 the next year and then scratch the following, and have been there ever since. It takes a lot of work not only to get there, but even more to remain there. The best advice I can give to anyone is going to the range does help, but you should spend most of your time hitting from a 100 yards and in and at the putting green. Most of the strokes come from this area on the course, and getting better from 100 yards and in will dramatically help your game.