I have two businesses
You DO need to be ready for up front costs
Your very first cost should be to take a class to improve skill.
The reason for that is if you want to secure any commercial clients ( regular , higher income) all clients need to see credentials.
The more you study, the more valuable you are.
This does not have to mean several years in school.
You can take Continuing education courses for cheap and they are only a few weeks long. Have several of them and you are interesting to clients.
While you are going to school, work as a freelance in your chosen field.
Use places like Craigslist to advertise your business and work for a little less then you will charge once you have your business going.
Customer service is the KEY here.
If people are not happy they talk. VERY LOUD.
Dont be ashamed if someone does not like your work. Do it over. You are in the business to make people happy. Drop your ego at the door.
Drop your slang at the door as well. Nothing is more of a turn off for a client then a kid who refuses to speak proper english. It makes you look uneducated and desperate. No one wants to hire a desperate person.
Practice all you can, where you can. Offer some of your services for free to people. This will not only increase your popularity and help get you known, but it will open the door to more work, which is where you get practice.
You can do it. Just dont think it will be easy.
It is a 24 hour job, but .. its 24 hours on YOUR schedule , at YOUR pace and no one else to govern you