Closing a swimming pool involves a series of steps to prepare it for the winter months. Here's a summary of the process:

1. Preparation:
   Gather necessary supplies like a pool cover, winterizing chemicals, cleaning equipment, and winterization accessories.
   https://www.poolzoom.com/category/in-ground-pool-winterizing-accessories.html
   

2. Cleaning:
   Thoroughly vacuum and brush the pool walls and floor to remove debris.

   Skim the surface to eliminate leaves, insects, and other floating particles.

   Empty skimmer and pump baskets to ensure efficient water circulation.
   

3. Water Chemistry:
   Test the pool water's pH, chlorine, and alkalinity levels.
   Adjust chemicals as needed to achieve the recommended winterization levels.
   

4. Shock Treatment:
   Apply a chlorine shock treatment to sanitize the water and eliminate contaminants.
   

5. Water Level Adjustment
   Lower the water level to the appropriate level, usually below the skimmer inlet.
   

6. Equipment Winterization:
   Drain water from the pool's pump, filter, heater, and other equipment.

   Disconnect and store hoses and accessories in a dry place.
   

7. Plumbing Preparation:
   Blow out the plumbing lines using an air compressor (for in-ground pools) to remove water.

   Seal the return lines and skimmer(s) with plugs or gizmos to prevent freezing.
   

8. Winterizing Accessories:
   Place an air pillow (above-ground pools) to prevent ice expansion damage.

   Install the pool cover securely as per manufacturer instructions.
   

9. Safety Measures:
   Ensure gates and fences are locked to prevent unauthorized access to the pool area.
   

10. Monitoring:
    Regularly inspect the pool cover for damage and remove debris to prevent sagging.
    

11. Spring Preparation:
    Remove and clean the pool cover as winter ends.

    Clear away winterization plugs or gizmos.

    Restore water to the normal level.

    Test and balance water chemistry in preparation for reopening.
    
    

These steps help safeguard the pool and its equipment during the cold months, making the process of reopening the pool smoother and more enjoyable when warmer weather returns. Always follow manufacturer guidelines and seek professional advice if unsure about any step.