Acid dyes are commonly used to color wool fibers. They are specifically designed to work in an acidic pH range, which is optimal for wool dyeing. Acid dyes are water-soluble and can easily bond with the wool fibers through ionic or hydrogen bonding.

Here's a general procedure for dyeing wool with acid dyes:

1. Prepare the dye solution: Dissolve the acid dye powder in hot water according to the manufacturer's instructions. The concentration of the dye solution will depend on the desired intensity of color.

2. Prepare the wool: Clean the wool by washing it with mild detergent to remove any dirt, oils, or sizing agents. Rinse thoroughly with water.

3. Prepare the dye bath: Fill a large pot or dyeing vessel with enough water to completely submerge the wool. Heat the water to around 140-160°F (60-70°C). Add the required amount of the dye solution to the water, stirring well to ensure it is evenly distributed.

4. Pre-soak the wool: Immerse the wool in warm water to wet it thoroughly before dyeing. This helps the dye to penetrate the fibers evenly.

5. Dyeing process: Gently place the pre-soaked wool into the dye bath, ensuring it is fully submerged. Stir the wool gently to promote even dye absorption. Maintain the temperature of the dye bath in the recommended range and continue stirring periodically to avoid uneven color distribution.

6. Heat setting: After the desired color is achieved, remove the dyed wool from the dye bath and rinse it under cool water to remove any excess dye. Then, either hang the wool to dry or proceed to heat setting to ensure colorfastness. Heat setting can be done by placing the dyed wool in an oven at a low temperature (around 200°F or 93°C) for about 30 minutes or using steam to fix the dye.

7. Final rinse and drying: After heat setting, rinse the wool again to remove any remaining dye. Use cool water until the water runs clear. Squeeze out excess water gently, taking care not to agitate or wring the wool. Lay the wool flat on a clean towel to dry, away from direct sunlight or heat sources.