Storm,  this is a great question!    I would begin with your best clients,  asking them for a referral to someone they know that could use your services; asking them for an introduction.   Ask for written references from your current clients that can be posted on your website.  

Yelp or Google referrals post are always helpful for those who may be looking for your type of business.  Providing an incentive to the company for the referral can help get this accomplished.  

In today's environment business owners are very savvy in researching new relationships. Also is your website up to date, is it mobile friendly?   Is your LinkedIn profile and business profile up to date?  Make sure you business is well positioned in the internet world.  

Good Luck!    MB