sentence: There's a person dressed in a black shirt doing a tutorial on how to powder skis to maintain them. sentence:  He begins by demonstrating how to sprinkle powder on the skis that are placed on a large red table in front of him. sentence:  He spreads the powder evenly on the gliding surface of the skis. sentence:  Then uses an iron to go over the powered surface to heat it slightly. sentence:  Then he shows how the skis look after the powder treatment.