It's pretty much a way to extend comic length. When you have drawn every thing, draw in the box to generate time for the reader to look at the drawing. When the box is drawn in (fill in the box slowly), erase everything and do more panels and use the same method. When you have reached desired length, erase all and put title picture along with which volume, part, or episode it is. Happy drawing! Remember to tell ur friends and spread the word!