First, stick a layer of vibration damping pad and a layer of sound insulation felt on the original wall, build a light steel keel, fill the keel cavity with a layer of sound insulation cotton or a layer of sound insulation cotton, and then seal the sound insulation board. Then use perforated gypsum sound-absorbing board for exterior decoration to achieve the effect of "external sound insulation and internal sound absorption". Use sticky powder and white glue caulking tape to paste the joints.