Measure the elastic around your waist and cut it to be about 1” longer than that. If you’re working with brown elastic, move on to step 2! If you’re working with white elastic, cut a piece of brown felt the same length and width as your elastic. Hot glue on top of the elastic.
Cut a piece of purple felt, about half the width of the brown but the same length. Along one edge, cut it to be wavy. Leave the other edge straight.
Glue the purple on top of the brown. When doing so, gather it slightly so it makes a ruffle.
Cut a piece of velcro just slightly shorter than the width of the elastic. Adhere one half to the front side of one edge of your belt, and the other half to the back side of the other.