Traffic from YouTube is pretty easy if you know what you're doing (like everything else)
Tube Toolbox is a great application for building a community on YouTube.
It has a pretty decent tutorial on how to get started, and you just gotta play around a bit and develop your own style of advertising.
Eventually you can just stop using the software for a specific channel and it will pick up speed on its own.
tubetoolbox.com
Or my ref link if generous
TTB