How do I get started riding on rollers? I want to train on rollers, and I figure once I get rolling it will be pretty easy, but how do I get my wheels turning fast enough to keep me upright before I fall over?
Until you get the hang of it, set up in a hallway, where you can brace yourself on the walls around you until you get up to speed and while you learn your balance. 

Other than that, you just have to keep trying.