For best results when obtaining a Structure Sensor scan (Pro app), one should wear swimwear, either a one-piece or a two-piece that has no additional loose or bulging material anywhere. Second best option is underwear, again without any additional loose or bulging material anywhere.
Third best option is skintight athletic wear. Please do keep in mind that we strongly suggest that whatever you wear should be absolutely skintight, as looser or bulging clothing will affect the results of the measurements significantly.
For other factors affecting measurement results, please see: Factors Affecting Measurement Results