LinkedIn has been the number one source of leads and clients for Gray Cat.  

Gray Cat has been built on word-of-mouth and referrals by creating profile(s) - both personal profile and Gray Cat company profile - that continually provide original content for its followers and connections.

Here is a short clip discussing this.

Want more ideas?  For more information on Gray Cat Learning Series, visit: https://www.graycatenterprises.com/gray-cat-learning-series