I had a channel with 300 legit subs in 2 months. I recently moved on to a new channel, but these are some of the strategies I used:
1) post to forums and social networks. (I used Yeousch forums, Twitter, Facebook, reddit, and 9gag)
2) Post videos as video responses to larger channels. (A good one is Tobuscus. He always enables video responses.)
3) box4box This is where you exchange spots in other channels sub boxes on their channels. You will gain some REAL subs from this.
4) be active in the community. (Dont you find yourself clicking on channels from the top comments of videos?)
5) Be a nice guy. If you are nice to people, they will often be nice back by subbing/liking videos/etc
Hope that helps.
