While performing ablution or taking a bath one should start from the right side of the body
باب التَّيَمُّنِ فِي الْوُضُوءِ وَالْغُسْلِ
Sahih al-Bukhari, Book of Ablutions (Wudu')(view book)
Narrated Um-'Atiya:
that the Prophet at the time of washing his deceased daughter had said to them, "Start from the right side beginning with those parts which are washed in ablution."
حَدَّثَنَا مُسَدَّدٌ، قَالَ حَدَّثَنَا إِسْمَاعِيلُ، قَالَ حَدَّثَنَا خَالِدٌ، عَنْ حَفْصَةَ بِنْتِ سِيرِينَ، عَنْ أُمِّ عَطِيَّةَ، قَالَتْ قَالَ النَّبِيُّ ﷺ لَهُنَّ فِي غُسْلِ ابْنَتِهِ " ابْدَأْنَ بِمَيَامِنِهَا وَمَوَاضِعِ الْوُضُوءِ مِنْهَا ".
Classification
Narrated 'Aisha:
The Prophet used to like to start from the right side on wearing shoes, combing his hair and cleaning or washing himself and on doing anything else.
حَدَّثَنَا حَفْصُ بْنُ عُمَرَ، قَالَ حَدَّثَنَا شُعْبَةُ، قَالَ أَخْبَرَنِي أَشْعَثُ بْنُ سُلَيْمٍ، قَالَ سَمِعْتُ أَبِي، عَنْ مَسْرُوقٍ، عَنْ عَائِشَةَ، قَالَتْ كَانَ النَّبِيُّ ﷺ يُعْجِبُهُ التَّيَمُّنُ فِي تَنَعُّلِهِ وَتَرَجُّلِهِ وَطُهُورِهِ وَفِي شَأْنِهِ كُلِّهِ.