Or you can take her to the bathroom sink, run the warm water, dip your fingers in it and just moisten those sticky little butt feathers over and over until the poo softens and falls off. If it seems icky to you, wear gloves, or just wash with soap real good afterward. If she's wet when you're done, take your hair dryer on low/warm and wave it quickly back and forth over her for a minute or two till she's dry. They learn to like that pretty quick! I call it their little butt spa. 
