Getting beginners to go
Many folks "doubt" their sailing abilities. Why not entice a group of likely prospects to sail on a boat with with you on daylight sails. Assume the role of benevolent captain and make them do all of the work. As they gain experience and confidence, they will be more likely to become adventurous and more likely to sail on their own bottoms in the company of other boats.
As they grow familiar with one another, those in the group will lose that "self-conscious" feeling that all inexperienced sailors have when others may be watching. Even with the best of conditions, sailboat handling presents more opportunities for embarrassment than anything else I can think of. Rather than risk looking foolish, many just don''t take the boat out.
Teach them that sailing is nothing more than a never ending series of problem solving exercises performed for the amusement of onlookers.
Once I figured this out, sailing became entirely different. Every time I "gaffe", I face the audience, doff my cap, and bow deeply at the waist. It always brings applause and cheers.
As a singlehander, I get many opportunities to perform -- and to learn.
Good luck on your quest to get these folks off their duffs.