How can you demonstrate your authority? Can you show endorsements from respected institutions or individuals? Can you feature testimonials or logos? Can you quote statistics or research findings? What evidence is there to support your claims? Are there other brands, organisations or authorities using your principles or products?
From Influence: The Psychology of Persuasion by Robert B. Cialdini
Try this
Find one credible endorsement, statistic or certification you haven't used yet, and weave it into your opening paragraph.
Ideas
Open a ten-minute sprint with Appeal to authority as your prompt.