Fun to watch but he needs to discipline her properly. First, she must be made to strip completely. Nudity contributes to compliance. Second, she must be taught to keep her hands away from her bottom by striking the errant hand with a hard paddle. Third, stop messing about with so many implements and develop a rhythm with each implement to build a sound all over reddening. Then let her squeal!!
When disciplining my dear wife I always prefer the rod. It is said that pain ennobles a young woman. And so, the planned infliction of pain by a whipping on the bare ass, as part of an educational process, acts as a catalyst that accelerates the maturation of a woman. It is a bitter medicine, but it must be administered with the utmost severity.