Viscose is a delicate quality, which requires gentle care. When needed, viscose can be washed in your washing machine at max 30°C. Note that when viscose gets soaked it will shrink and wrinkle. This is natural.
Do never stretch, squeeze or hand-wring wet viscose as it is close to being just as fragile as a wet newspaper. It loses up to 50% of its strength when wet. Instead, shake it carefully and lay down to dry on a towel to avoid deformity.
Steam or iron on the dry viscose on lowest heat and the viscose will come back to its natural size and form again.