I found it helpful to just quit my job, get a divorce and just play 15 hours a day. I got rid of all of my friends and just stopped paying bills, I only spend money on alcohol and cigarettes now. Within about 7 weeks I went from a 300 rating to a 325 rating, I'm expecting to be at 350 by the end of the month. So I agree, if you keep playing you will definitely get better, just look at me.
Oh, and the max amount of XP daily really through a wrench in my plan.......................