I see. I am not in the same field so some of what I say may not apply but as a designer I'm always looking to partner with people who can create websites to specs. Maybe other developers can chime in but I can give a few tips that have worked well for me:

-if you don't have any current leads, ask around. Colleagues, family, friends, people you know. Just get the word out so next time a relevant topic comes up in a conversation you're the first on their mind. Also get a profile on freelancing sites. - Don't compete on price. Offer solutions not services. - Make a portfolio of your projects, even personal ones and talk about your role in those projects, goals, outcomes etc. - listen to freelancers podcasts - art of value is a good one. - get to know people in complementary fields like designers. Your source of leads could be from a business, an agency or a designer.. even copy writers. - start on a paid gig. Personal projects are alright but developers need paid gigs in their portfolios. - start now, somewhere, anywhere. Some people never start.

If you are beyond these tips already, great. If not, wish you the best of luck!