So, a lesson in terminology first. You’re too young and inexperienced to be freelancing. Freelancing involves approaching companies and offering to do things like build websites for them. There’s a sales process involved because you’re offering a more complete service. You’re just too young to make freelancing work for you.
What you want to be doing instead is contracting. Contracting involves approaching someone that hires contractors and asking for a gig. The company or person you’re asking will look over your skills and if he has something for you, you’ll start pretty much immediately.
When you’re freelancing, you’re selling business solutions. When you’re contracting, you’re selling your skills.
That said, how would you go about becoming a web development contractor? Well, the best way I found was to frequent a coffee shop and talk to all the people there that are working on their laptops. This is how I got into web development 5 years ago. I eventually met my good buddy Theo Rosendorf of Article and he put me to work on a project that had just come up that needed my skills. Theo is a freelancer. I contracted for him.
I made enough on that project to buy a MacBook Pro. And it helped kickstart a career that now pays me six figures.