Actually, you don't wanna aim for "keeping it going", you want to rise higher. This is when you want to aim for gateway videos. Decently short, mass-appealing videos. I don't like tooting my own horn, but look at my latest video entitled "the full revive bungaloo". It went viral within 1 day, and came to be my most viewed video ever because of Reddit.
You're at the stage where you're big enough to aim for gateway videos, now put that to good use, and once you think you're ready, also use Reddit.[DOUBLEPOST=1372248485,1372248416][/DOUBLEPOST]
Well that's exponential growth, I cover it in another guide of mine. You see the bigger you are, the faster your growth. Basically at some point, every of your videos will be gateway videos, automatically.