Complex sentence: Snoopy decides takes out one book, a book on magic, which after reading, influences him to hold a Vaudeville show (under the stage name "The Great Houndini"), recruiting Marcie as one assistant and announcer, and Sally as his silent assistant.
Split into simpler sentences: Snoopy decides takes out one book, a book on magic, which after reading, influences him to hold a Vaudeville show (under the stage name "The Great Houndini"). He recruits Marcie as one assistant and announcer, and Sally as his silent assistant.