The first ones just look like random scrapes of chocolate that have been folded over while still pliable. The side chocolate panels are melted chocolate spread out on a cookie sheet or acetate paper, chilled till just set and then cut into strips or rectangles that are measured to the height of your cake and cut with a bench scraper, chilled till firm and then attached to an iced cake with a dab of melted chocolate. On the bottom curls, white and dark. If you slide the bench scraper just barely under the chocolate and just let it curl slightly, push straight away from yourself to begin the curl and then push at an angle to the left or right rather than straight it will curl like this.
For the chocolate ruffles I did on this cake, I froze a gumpaste cel board in the freezer, took it out and spread it with tempered chocolate, it sets up almost immediately so you have to work fast. But you slide a scraper under the length of the chocolate and you can lift it right off the board, accordian pleat it from the narrow sides with both hands, fold in half and pinch the bottom to make a fan shape, Then open up the top ruffles a bit. The sides of this cake are a chocolate wrap.