The Messenger of Allah ﷺ forbade two ways of wearing a garment. The first is the Samma wrap, which is to drape one's garment over one shoulder so that one side of the body is exposed with nothing covering it. The second is to sit wrapped in one's garment with the knees drawn up, with nothing covering the private parts.
نهى رسول الله ﷺ عن لبستين: اشتمال الصماء، والصماء: أن يجعل ثوبه على أحد عاتقيه، فيبدو أحد شقيه ليس عليه ثوب: واللبسة الأخرى: احتباؤه بثوبه وهو جالس، ليس على فرجه منه شيء.
Bukhari narrated it in the Book of Clothing (5820) and Muslim in the Book of Trade (1512), both from the hadith of Yunus, from Ibn Shihab, who said, Amir bin Saad informed me, that Abu Saeed Khudri said, and he mentioned it. The wording is Bukhari's, and Muslim abridged it.