Sing well and often, in front of as many people as possible. Enjoy it as much as possible, since the odds of phenomenal success are very slim. Don't even bother unless when you sing, you always have several audience members tell you how great you are. And no, your mother doesn't count.
I think youtube and soundcloud are great mediums to gain following. Moreover, try putting your videos on instagram and facebook as well. Make sure that you use a high quality camera to record. If you sing really well, try to participate in a singing competition. Moreover, continue participating in competitions at your school/college level.
At first, you do whatever you can to get recognized, and then if you do you work your ass off, making new and original pieces that people want to hear.. if you can manage this, then you'll cross your fingers and hope, that people don't get bored of the things you create.