If I can recall correctly, I have a friend (17/18 at the time), who started a business with no money, other than being gifted with some servers, a domain and a website because he's simply a great guy. He started advertising that he was giving out free servers for people on a game forum (think Minecraft servers). This was simply a strategy to gain customers and recognition (it was very niche so he would have easily gained traction). After a while, he decided to ask for monthly payment from those, who are using his servers. Those who refused had their servers taken away and he quickly found new customers to sell them to. Whilst doing this, he improved upon his product by making it more easier to use (streamlined the process, through programming it - I'm not going in to details) and this caused a huge increase in growth, eventually becoming the top three server providers for this game. His competitors even copied his process. Overtime, it grew to the point, where he was selling many servers to other smaller companies to sell those servers, started doing webhosting and started selling servers for other games. He was earning $200+ (or was it euros?) per month. The company closed down because he didn't want to hire a lawyer to legalise his company - he got a lawsuit because he was making a lot of revenue. I'm not sure if I should mention but, prior to this, he did have a lot of experience working on all sides of this "industry", by working for his competitors, whom he surpassed (one of the top three), as a moderator, advertistor, programmer, recruitor...
You could do that.
Or, you can do what I am doing, which is working part-time, save up and then invest.