The Prophet ﷺ loved to begin with the right side when putting on his sandals, combing his hair, performing ablution, and in all his affairs.
كان النبي ﷺ يعجبه التيمن في تنعله وترجله وطهوره، وفي شأنه كله.
Bukhari related it in the Book of Wudu (168), and Muslim related it in the Book of Purification (268), both through the route of Shuba, from Ashath bin Salim, from his father, from Masruq, from Ayesha, and he mentioned the hadith. Muslim also related it through the route of Abu Ahwas, from Ashath, by the same chain, and in it, "The Messenger of Allah ﷺ used to love to begin from the right in his purification when he purified himself, in his combing when he combed his hair, and in his putting on sandals when he put them on." End of quote.Shuba said, Then I heard Ashath in Wasit say, "He loves to begin from the right in all his affairs." He said, Then I heard him in Kufa say, "He loves to begin from the right as much as he is able."