The way that I see most people do it, is by simply making a vid that says visit this site for more information, and then links you to your site.
Now on the other side your site is linking to your youtube which is linking back to yourself through videos. So now take that group of subscribers you have and make sure to have your website shown so they visit your website.
It's basically linking to yourself and back again lol.
That's the way I plan on doing mine, but I hardly post comments on any videos unless their of my friends or subscriptions.