Dust ruffles are practical (they hide the stuff under the bed) and pretty (they finish a bedroom nicely) and annoying (they never stay where they are supposed to and are often a little too short or a little too long) and sometimes hard to come by (in the right color, mattress size, and length).
I fixed every one of those problems. You're welcome.
One of the bedrooms needed a black dust ruffle, full, ruffled-not-tailored, and with a 20" drop. Impossible to find in town, easy to order online, although as a 21" drop. After thinking through the steps of making a perfect dust ruffle for my master bedroom redecorating project, I came up with this method of altering a purchased dust ruffle to make it easier to install and live with. No velcro, no hot glue guns.
Keep in mind that a dust ruffle, or dust skirt, has two parts: the "deck" which is the flat piece of fabric that covers the box spring, and the ruffle, or skirt, which might be pleated or gathered. Either style of skirt will work with this method. You need your dust ruffle, shears, and a package of twisty pins, otherwise known as upholstery pins. You'll find them at fabric shops, dollar stores, and sometimes department stores.
1. Cut the center of the deck out of the ruffle by leaving a 4 inch border on top of the seam where the dust ruffle is attached. In my picture the ruffle is black, the deck is white (they usually are), and I have left a 4 inch border all the way around the dust ruffle.
4. Work your way around the bed, paying attention to the hem and how even it is along the floor. Use as many pins as needed to keep the ruffle from shifting.