Ruffles change an outfit by adding volume in a particular place. Sandro's Ruffled Pieces edit gives you a way to make that detail the focus, keeping the remaining shapes simpler. Volume is easiest to balance when it has a clear location. A detail near the upper body may call for simple trousers, while movement lower in the outfit can leave room for a simpler neckline and shoulder line.
If your starting point is a dress, let its silhouette decide how much else to add. For a separate, pair it with quieter clothing and avoid crowding the same area with accessories. The result can feel expressive without becoming overcomplicated.