Since my channel is a gaming channel, I asked one of my favorite youtuber (sacriel42) what his advise was starting out. I initially asked, "when you started out did you worry about search engine rankings for your videos?" He was kind enough to reply and stated he did not worry about SEO at all. Just focus on making QUALITY videos and promoting them on forums, Facebook, twitter and any other social media you can think of. I took his advise to heart and it has paid off. I've only had a channel for a few months but I have a loyal fan base and my stats are steadily and exponentially improving. So my advise QUALITY and they will watch and sub.