first of all you need to put up content regularly so people will have a need to check back.
second you may want to contact some of those guys and ask them to watch your videos or perhaps put a good word in for you. (provided you have enough content and dont suck). i've seen them put a link to some other users videos if they feel impressed enough and that will get you pageviews.
if its interesting those pageviews will turn into subscribers which in turn can land you in some search results on the right bar. if you get popular enough you might be lucky enough to get a front page slot on someone that views alot of game walkthroughs.
basically what i'm saying is that its going to take awhile to get people to start coming to your channel but if you work at it, talk to some other users, make video responses and post them on similar walkthroughs in the comments then people will start viewing your channel. of course this is provided you have more than 1 video. i would suggest having at least 5-10 videos up and a steady influx of new videos to keep anyone who does show up entertained.