How to use and achieve a 100% lights blocks?Step1: Wear the Sytmhoe sleep mask wellStep2: Adjust the length of strap to the most comfortable position to fit your head wellStep3: Adjust the nose flap to fit your bridge of nose wellHow to Washing and Maintain?- Please wash the sleep mask when you receive it, machine washing is not suggested that may shorten service life.- Please wash it with clean water that is not above 40℃, then let it dry naturally- Please wash it in time when it touched with sweat, tears or viscous skincare productsSytmhoe Worry-Free Product Guarantee- Sytmhoe has a professional after-sale team, if you have any dissatisfied point, please feel free to contact us, we will give you a satisfactory solution