Well I Have One Question How Did You Get Youre Subscribers Because I Woud Want To Have The Same amount As You!!
Well I don't know but I can tell you some pointers
, Try make best quailty you can, Upload daily or weekly, Be friendly on camera and off camera, Allways responds to you comments, Don't listen to the haters and thumbs down, Only listen if someone saying something to try improved you video, Upload videos on Google Plus, Twitter, Facebook, MySpace, etc, Use Tags, Watch you subscribers videos and give comment back but be real and make sure you do watch the video, and don't worry about how many views, likes, subscribers you have and don't prepared youself to others or saying you going be that person or better, and biggest one for me is Be Yourself don't be fake you or be someone else People will notich you try to be someone else or people call your as "Fake". Hope this help!!!