These illustrations are from a women's magazine dated July, 1879 called "Peterson's Ladies National Magazine". Within the pages are everything a home maker could want. This includes a clear illustration showing the mechanics of the then current bustle drapery. That month the magazine featured a bustle with a two panel draped front, and a bustle train in the back. All of this would be fastened at the waistline, and covered with the longer basque bodice 'jacket'.
The bustle draft shown here takes alot of the mystery out of bustle arranging, showing how it is really just a puffy apron worn over the underskirt. It's kind of amazing to think that this might be all a woman might have had as reference in making her own fashionable costume. Ideally she got some help, and was able to copy an existing bustle that her cousin had tailor made in Boston, rather than reinventing the wheel on her own!
What you aren't seeing here is that most successful bustles where draped on the bias, so that those front corner 'points' are probably right angles where the selvage and cross grain meet. The bustle pleating was similar to bunting, ruching up the fabric to create the necessary drapery.