Here are some detailed steps：

Waxing Method:

1. Choose wax suitable for natural fibers like cotton or canvas.
2. Create a double boiler to melt the wax gently.
3. Submerge the fabric in the liquid wax solution.
4. Ensure the fabric is fully saturated.
5. Hang the clothes to air dry.

Alum and Detergent Method:

1. Mix hot water with unscented powdered detergent.
2. Soak the fabric in this solution to create a foundation for waterproofing.
3. Hang the clothes to air dry.

Waterproof Coating Spray Method:

1. Use a durable water-repellent spray suitable for all fabric types.
2. Wash and dry the clothing before applying the spray.
3. Place the clothing on cardboard to avoid spills.
4. Apply the spray evenly and let it dry for at least 2.5 hours.

Of course, you can also opt for waterproof clothes.

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What are some common mistakes to avoid when washing waterproof clothes?

Some common mistakes to avoid when washing waterproof clothes include:

Using Too Much Detergent: Excessive detergent can leave residues in the fabric, attracting water and reducing waterproofing. Use a small amount of detergent and rinse thoroughly after washing.

Not Heat Treating the Garment: Forgetting to heat treat the garment after washing can lead to the outer fabric absorbing water, making you feel cold and clammy. Heat treat the garment in a tumble dryer or with an iron on a low temperature setting to reactivate the water repellent treatment.

Using Standard Laundry Detergent: Regular detergents can break down the fibers and strip the fabric of its waterproof coating. Always use a cleaner specifically designed for technical outerwear to wash waterproof jackets.

Not Following Manufacturer's Instructions: Always read and follow the care details on the garment or manufacturer's instructions for washing waterproof clothing. Each brand may have specific recommendations to maintain the gear's functionality.

  By avoiding these mistakes and following proper care instructions, you can effectively wash and maintain the waterproof properties of your clothing.