Adding case studies to your website
A great way of sharing what you do and how you do it is through case studies and showcasing the clients or customers you serve and provide for.
Adding case studies to your website also creates great SEO material, creating a keyword friendly case study will add more content for your website to rank with.
As well as that it is perfect content for you to share on your social media, remember social media isn't all about selling your service it's also about letting people know what you offer and how you offer it.
As well as a case study you can add a testimonial in there too from the client to bolster whatever claims you are making.