Before using K18 x Future Society Leave-In Molecular Repair Hair Mask 50ml, shampoo your hair and do not apply hair conditioner. Then, towel-dry the hair. Dispense 1-3 pumps of product onto your hands (depending on your hair length and density) and rub them together until the product turns white. Then, apply it to the hair, starting at the ends and working up towards the roots. Let it sit for 4 minutes. Do not rinse out. Finally, comb the hair, add any styling products, and style your hair as usual. For best and progressive results, use for 4 to 6 washes post-salon service and then as needed.