How do you gain a large online following/presence?

[Niall]

I am in need of some very intelligent online marketers! If you have any good ideas, please feel free to share them, I need everything I can get!

So the thing is... I'm a 16 year old musician from South Africa. My goal is to get discovered by a large record label/company (preferably in America) that can help fund my career and promote my music. I know that if I send these labels a demo tape, chances are they will throw it in the trash as they don't have time to listen to unsolicited material, plus the fact that they probably receive thousands of submissions every single day. Everybody wants to be a star!

I've realized that many musicians have gained the attention of a record label by having a large online following or having a strong internet presence (example: Justin Bieber) because the label realizes that if they invest into this artist, they know that the already large fan base owned by the artist will buy his music automatically. I have established many social platforms including my own website, Facebook, YouTube, Twitter and ReverbNation. But for some reason, none of these things have generated a substantial amount of buzz... The strange thing is, I've become quite a celebrity at my school due to the discovery of my YouTube videos (the school has 1800 kids by the way) so I can't understand why my internet ratings haven't soared yet...

So i'm asking you, is there anything else I can do to up my internet game? I know there is no miracle pill to make me an internet sensation, but I need to keep working on some concrete strategy in order to get anywhere with my music career. Please share your knowledge with me, I will be forever grateful! Thanks again