what i do is i "weave" the needle through, rather than make my poor little fingers make and hold the crease, lol. here are some pictures. i just made a tuxedo bow but i think it may be used on those pretty boutique bows. just make sure the needle weaves through all of the ribbon.
the first pic is of the front. second, of the back, and the third is when you just pull tight, wrap around, and secure.
then i just cover the string part with a bit off ribbon.
excuse the dirty ribbon scrap i used and the unsealed ribbon ends. just made this as a quick tut.