First, don't beat the interlayer, try to spread the wool interlayer flat and brush it clean, and don't beat it by hand, resulting in uneven distribution of wool in the east and west.
Second, dry it in time after washing. Don't leave it in a damp place for a long time. It's best to let it go and expose it directly to the sun.
Third, to prevent mildew and moth, we must keep warm.