Each time I want to start a business, I feel excited in the beginning but when I think about sales, I feel overwhelmed and I bail out I'm a software engineer with full time job, I identify a business opportunity, I do all the planning, I create business model canvas / plan in few days, I do all the planning following lean approach , set a schedule etc. I know my ideal customer and market, briefly all the theory is done, but when it comes to taking actions, talking to people and get some clients on the phone, I feel overwhelmed, and afraid to get out of my comfort zone I end up dropping the ball quickly and the idea falls in the cracks.
I think that is great that you have all of the "hard" stuff hashed out (the theoretical items and target market identification). Now it is time to put your plan into action and do what you started the business for; to get clients.
I find it first beneficial to ensure that I believe in the product that I have. Obviously you believe in it enough to do all the work thus far and look for validation to do what is next. Having belief that it can be successful will show you that there is nothing to fear, one person is bound to like the idea. From all of those who don't listen or don't enjoy your product, chalk them up as learning lessons and move on.
Surely, you have faced a similar position of being afraid to get out of your comfort zone. Inevitably, you eventually got out of it and you grew from it. Entrepreneurship is all about growing; I look forward to you and your business growing.
The tactic that I found the best to go out and telling potential clients about my company/me is telling someone that I am going to do it. "Hey, I am going to pitch my business to this Friday," I have found myself saying to friends/family. Well now, I really have to do it; I can't lie to them. Saying something and fulfilling that expectation is a great way to overcome this sort of fear that I, and numerous of other entrepreneurs, have.
I wish you the best of luck moving forward, I would love to talk some more and help this idea become a reality.