Do couple of small sites for free. Also start giving free demo website/ sample sites to clients. If they don't buy, well you can add to your portfolio to show it to other clients.
In no time you will have lot of sample sites u can start showing to prospective customers and your conversion rate will increase. And slowing afterwards you can stop giving away free sample demo sites etc
Once you are established ... My only advice would be :
Over the time one thing I Learnt; never work without a deposit, once u ask for a deposit first, the bogus client would disappear in no time!!
Getting stated is imp.... Once the ball starts rolling its on u....
Start small, then expand gradually. Find what clients in your local area want and demand, provide this at a price they don't mind paying, then work on recommendations to slowly expand your clientel. This is the secret to being succeful. Once you have enough clients gradually increase your price offering better services, and from here, continuesly evolve your clients website into further enhancing their online traffic.
Start by doing a few projects and gathering them in an online portfolio. Design a professional website for yourself where you can display this portfolio and then advertise it in any relevant social media platforms, forums, blogs, and websites. Make sure you advertise yourself in places that get global traffic. This should get the word of mouth going about your business.