Become a respected industry expert – this takes time

Select a market segment which you have some in-depth knowledge from past experience.
Research what is happening in that industry, write articles for publications, or seek public speaking engagements, speak out on industry issues, write Letters to the Editor.
Use social media and Linked In to signal your position as an innovator in your industry.
Keep your name and brand prominent.

Get referrals

This is an excellent way of winning more customers. Ask your satisfied customers for a referral. "If you know someone who would benefit with what I have told you about I’d appreciate the reference."

Form friendly alliances

Join up with a friend or another organization, perhaps one with an established customer base, especially one that complements or supplements your product or service.
For example a landscaper could link up with a builder, a handyman could link up with a cleaner or a fitness company could link up with a dietician.
Shared customer bases can be very productive.