1. Prepare tools and materials: caustic soda, water, rubber gloves, water pump, plastic bucket, long-handled brush, etc. 2. Wear rubber gloves, pour a certain amount of caustic soda into a plastic bucket, add a proper amount of water, and stir well. 3. Pour the caustic soda solution into the sewer and let it stand for a period of time to allow the caustic soda solution to penetrate into the pipeline. 4. Brush off the dirt in the pipeline with a long-handled brush, and at the same time, add an appropriate amount of water to flush the pipeline. 5. Pump the sewage in the pipeline and repeat the above steps until the sewer is unblocked. 6. Precautions: Wear rubber gloves when using caustic soda to avoid contact with skin; The caustic soda solution should not be too much, so as not to damage the pipeline; Pay attention to safety when using the water pump to avoid sewage splashing on your body.