I chose buying an already established company in our community for 25 years, over going to college. I still had to "pay to learn" you might say, because the first thing I needed to do when I bought it was update all the equipment and start over in the aspect, but I still had the customer base to keep me paying my bills.
Did I have to pay for my education in this business, yes...seminars, trade shows, trial and error, BUT I am working in the field in which I educated myself in. I would recommend what everyone else said, if graphic design, or some kind of setup that already taught you how to do this wasn't what you got a degree in, you should either A) focus on whatever that degree was in, and not throw money into the wind trying to teach yourself all over again (because it's cut throat, it's not easy to profit and support yourself in this business like it was even 5 years ago) or B) go get a job in a shop for a while if this is something you are wanting to do, and learn before you jump in head first.
The internet has helped and killed this industry, but our country also has a walmart mentality, where they want it right now, and they want it dirt cheap, and "professionals" in our industry have created that effect for customers. That's why there are crap signs all over the place. They are just bottom dollar, arial black one color yard signs.
The money is in things OTHER than yard signs generally, and any of the big guys here will tell you that. Not saying you can't make it happen, but you'll have to have one heck of a business plan to invest $400 with no customers and make it support you and all your overhead and bills, advertising, supplies, telephone, computer, internet etc.