First thing you want to do obviously is to get a portfolio together showcasing a variety of work or whatever you are best at. Then I would look into putting up a website with you own domain name and hosting and have some one code you a one page portfolio site with just your work and contact information.
Then start doing research on how to find work. Maybe start off doing some stuff locally as Distill said and once you have a few paid gigs under your belt start looking into more online promotion. There are plenty of free ways to advertise your services online.
Keep an eye on my blog
www.youthedesigner.com I post about a lot of websites that can help you.