If I've said it once, I've said it a thousand times, or approximately forty-three times before, if you want to sell underwear, find Irina Shayk in the phonebook, ring her up, hire her to model your silky little bras and panties, and you will be successful. You don't need to read a book on how to sell, let alone go to one of those silly places they call schools to get a piece of paper. Just hire Irina, a photographer, and set the lighting and you will be on the cover of Salesperson Monthly being heralded as a genius.
Heck, this goes beyond lingerie. Hire Irina to be behind the counter of your church bake sale and every man within five counties will be buying pies to support your cause. She's like magic in a body. Enjoy.