Be persistent

Don't be a pain in the ass. I am definitely Not saying that. However, if you want to show that you are truly interested in something--a class, a job, a room at the cool house, writing the next Great American Blog--keep at it. Turn up once a week, put some time in daily, whatever it takes (without being a PITA). People tend to take you seriously if you are willing to invest time in something that doesn't pay off immediately.