How you can stand out: there's as many answers to that question as there are people. Best advice: be yourself. Know your own strengths and weaknesses, and sell your personality and approach to business as much as you sell the service.
What kind of training you'll need: there are, and are not, courses that teach you how to do this. Courses in running a small business could be helpful. A course in speech and / or communications will be your best bet, though. You'll be answering client questions, so you'll need to know how to understand their question, answer it thoroughly and well, and leave your client feeling like they've got an ally of sorts. Yes, you'll want to learn the basics of how to operate the control panel, and if you're not a researcher at heart, you'll learn to be (just to answer your clients' questions.)
Web hosting is a recurring-service business. You have to be there not just today, but next year, the year after that, and so forth. Be ready to make sure that whenever you are going to be away from your computer, someone will still be able to support your clients and answer their questions.
What you'll need to get started:
* a basic business plan
* a web hosting reseller account - less cost and less commitment than a VPS; and if you find that you plan to keep doing this, you can migrate to a VPS or a dedicated server when you have the client base
* a way to accept client payments online (Paypal, 2checkout are good widely accepted "starter" options in North America and a good chunk of Europe)
* a good research starting point (this forum is one of them; Google is another)
* a whole lot of patience
You may want to add embellishments, like: a way to resell domains, actual billing software, a client mailing list and / or forum, live chat software, what have you. But the above list will get you started with the absolute minimum.