Providing a 15000-word article here would exceed the output limit for a single response, but I can provide the structure and key points for the expanded write-up.

1. Understanding Your Furoshiki Cloths

   • Detailed background and description of Furoshiki Cloths.
   • Different types based on fabric, size, and design.

2. Day-to-Day Care and Maintenance

   • Proper ways of folding, unfolding, and storing.
   • Avoiding excessive wrinkling or creasing.
   • Protection from sunlight, dust, and pests.

3. Shake it out and Air!

   • The importance of airing Furoshiki cloths to prevent molding and bad odors.

4. Spot Cleaning

   • Methodology for identifying the type of stains.
   • Safe and effective ways for spot cleaning.
   • Precautions to be taken while stain removal.

5. Washing Your Furoshiki Cloths

   • Guideline for machine wash: suitable cycle, temperature, and detergent.
   • Emphasize hand washing: temperature, detergent, and technique.
   • Pointers on fabric softeners and their influence on the cloth’s longevity.

6. Drying Furoshiki Cloths

   • Highlighting proper drying techniques: line drying, shade drying, and when to tumble dry.
   • The consequence of not adhering to drying guidelines: shrinking, fading, etc.

7. Ironing and its Rules

   • The significance of ironing Furoshiki cloths.
   • The safe temperature for different fabrics.
   • Importance of using a clean iron and technique.

8. Repairing and Preserving Furoshiki Cloths

   • DIY tips for mending minor wear and tears.
   • When to consult a professional for repair.
   • Methods to preserve the design and color of the fabric.

9. Caring for Special/Designer Furoshiki Cloths

   • Special care for luxury or designer Furoshiki cloths.
   • Unpacking, storing, and maintaining specialty Furoshiki.

10. Seasonal Furoshiki Care

    • Care instructions for different weather conditions – summer, winter, humid climates.

11. Furoshiki Etiquette

    • Guide for presenting and receiving Furoshiki-wrapped gifts.
    • The method of returning a Furoshiki gift wrap.

12. Sustainable Care

    • Encouraging sustainable care practices for Furoshiki cloths.
    • Environment-friendly cleaning products and methods.

Each of these sections can be elaborated in-depth with SEO-friendly keywords, expert quotes, personal anecdotes, cultural details, facts, statistics, and engaging stories. Relevant subheadings can be used to break the content into manageable pieces for better reader navigation and understanding. This proposed structure can easily be expanded to a 15000-word comprehensive guide on caring for Furoshiki Cloths.