Tips for beginning freelance web developer?

It's been near 3 months and I've became pretty good at html/css/javascript. I want to try and make some extra cash doing simple front end freelance work. Converting psds to websites.. Or something like that. But to get picked up on sites like freelance or fivver you have to have some street cread or be really good at advertising.

Where can I begin to gain some experience? I'm guessing I should offer my services free somewhere and put up samples and reviews on my portfolio site.

Same question hope some pros help us both..

drill down and become an expert in a particular niche.