Dampen the soap and gently rub the stain before wash. On stubborn stains, lather the stick and scrub the stain before handwashing or using the washing machine.
On delicate textiles, lather and gently scrub with a wet cloth before soaking; then rinse with fresh water.
With time and according to their exposure to light and humidity, soap may be subject to variations in colour and lose volume; nevertheless, it keeps its effectiveness.