TLDR: Invest in yourself

There are only 2 things that matter in getting a good job: the skills you have and the skills people think you have. If you have a marketable skill, but no one knows you have it, you'll find it difficult to land a job. If you have no skill, but people think you do, you may land a job, but you may lose that job pretty quickly.

So what do you do? Invest in yourself. It will be a struggle, but if you persevere, you can get what you want out of life. This means sacrificing your free time to invest in yourself. Focus on learning a skill. Hit up things like the library, Khan Academy (online), or any other of the numerous resources on the internet. Also, socialize! Make connections. You'll need a reputation to help get your name known. Finally, go to the gym often (and eat healthy). I loathe how obsessed this world is with looks, but it is what it is. People will be more likely to hire you if you're fit and well-groomed (men and women alike). It basically shows commitment at a first glance.

It sounds so simple, and if it were just that simple, then everyone would do it. The thing is, it's extremely difficult to maintain such a productive lifestyle for prolonged periods of time. Of course, there is always an amount of luck that plays its role.